Bis piperidyl carboxylates

ABSTRACT

New 1- and 4-substituted piperidines are stabilizers for organic material. They are produced by reacting corresponding 1-substituted piperidinols with acid chlorides or corresponding 4-substituted piperidines with a compound introducing into the 1-positon a residue.

This is a divisional of application Ser. No. 310,031 filed Nov. 28,1972, now abandoned.

The present invention relates to new piperidine derivatives, and inparticular to new piperidine derivatives substituted at the 1- and 4-positions and having value as stabilisers for polymeric materials.

In German Patent Specification No. 1,929,928 there are describedcompounds having the general formula: ##STR1## WHEREIN R₁ ' and R₂ ' arethe same or different and each is an alkyl group, or, together with thecarbon atom to which they are bound, they form a saturated alicyclicgroup or a group having the formula: ##STR2## n' is a whole number from1 to 3 inclusive; and when n' is 1, R₃ is an acyl group derived from analiphatic, alicyclic or heterocyclic mono-carboxylic acid, anN-substituted carbamoyl group derived from an N-substituted carbamicacid, an N-substituted thiocarbamoyl group derived from an N-substitutedthiocarbamic acid, a monovalent group obtained by removing an hydroxylgroup from an oxo-acid, an alkyl group, a cycloalkyl group, an aralkylgroup, an aryl group or a group having the formula: ##STR3## wherein R₁' and R₂ ' have their previous significance; when n' is 2, R₂ is adiacyl group derived from an aliphatic, alicyclic, aromatic orheterocyclic dicarboxylic acid, a dicarbamoyl group derived from adicarbamic acid, a bis-thiocarbamoyl group derived from abis-thiocarbamic acid, a carbonyl group, a divalent group obtained byremoving two hydroxyl groups from an oxo-acid, an alkylene group, anarylene group, or an arylenedialkylene group; and when n' is 3, R₃ is atriacyl group, derived from an aliphatic, alicyclic, aromatic orheterocyclic tricarboxylic acid, a tricarbamoyl group derived fromtricarbamic acid, a tris-thiocarbamoyl group derived from atris-thiocarbamic acid, a trivalent group obtained by removing threehydroxyl groups from an oxo-acid, an alkanetriyl group, arenetriyl groupor an arenetriyl trialkylene group.

We have now found that certain piperidine derivatives substituted in the1- and 4- positions are effective stabilisers for polymers, especiallyagainst photo- and thermal degradation.

According to the present invention, there is provided a compound havingthe formula: ##STR4## and their salts wherein n is 1, 2, 3 or 4; R₁ is amonovalent residue and is an alkyl residue having from 1 to 20,preferably 1 to 12 carbon atoms, an alkenyl or alkynyl residue havingfrom 3 to 20, preferably 3 to 12 carbon atoms, an aralkyl residue havingfrom 7 to 12 carbon atoms, or a residue having the formula: ##STR5##wherein m is 1, 2 or 3, R₄ is hydrogen, methyl or phenyl residue, X₂ ishalogen, cyano, ##STR6## --COR₅, --CO.OR₅, --CO.SR₅, or --CONR₅ R₆ andX₁ is hydroxyl, halogen, cyano, --OR₅, ##STR7## wherein R₅ is an alkylresidue having from 1 to 20 carbon atoms, an alkenyl residue having from2 to 20 carbon atoms, a cycloalkyl residue having from 5 to 12 carbonatoms, an aryl residue having from 6 to 11 carbon atoms, an aryl residuehaving from 6 to 11 carbon atoms or an aralkyl residue having 7 to 11,preferably 7 to 8 carbon atoms when R₅ is joined to a nitrogen atom,also hydrogen and

R₆ is preferably hydrogen or an alkyl residue having from 1 to 4 carbonatoms, or

R₅ and R₆ together with the nitrogen atom to which they are bound form a5- or 6-membered ring which contains no other heteroatoms or containsone or more other heteroatoms, or

R₁ is an acyl group ##STR8## wherein R₇ is hydrogen, an unsubstitutedaliphatic or substituted aliphatic residue having from 1 to 20 carbonatoms, an alkenyl or alkynyl residue having from 2 to 20 carbon atoms, acycloaliphatic residue having from 5 to 12 carbon atoms, an araliphaticresidue having from 7 to 14 carbon atoms, an aromatic residue havingfrom 6 to 20, preferably 6 to 12, carbon atoms or an heterocyclicresidue, or

R₁ is a carbamoyl or thiocarbamoyl residue having the formula: ##STR9##wherein X₃ is --O-- or --S--, R₈ is hydrogen or an alkyl residue havingfrom 1 to 4 carbon atoms, and

R₉ is hydrogen, an alkyl residue having from 1 to 20 carbon atoms, analkenyl residue having from 3 to 20 carbon atoms, a cycloalkyl residuehaving from 5 to 12 carbon atoms or an unsubstituted aryl or substitutedaryl residue having from 6 to 12 carbon atoms;

R₂ is an alkyl residue having from 1 to 4 carbon atoms, an alkenyl oralkynyl residue having 3 to 20 carbon atoms, preferably 3 or 4 carbonatoms, a cycloalkyl residue having from 5 to 12 carbon atoms, an arylresidue having from 6 to 11 carbon atoms or an aralkyl residue havingfrom 7 to 9 carbon atoms or preferably hydrogen; and when n is 1, R₃ isa monovalent radical having the same significance as R₁, or R₃represents a monovalent group obtained by removing a hydroxyl group froma sulphinic acid, a sulphonic acid, a phosphorus containing acid or aboric acid, or R₃ is an aryl residue, a cycloalkyl group having from 5to 12 carbon atoms, or a residue having the formula: ##STR10## whereinR₁ ' is hydrogen or R₁ ' has the same significance as R₁ ;

When n is 2, R₃ is a divalent residue and is an alkylene residue havingfrom 1 to 20 carbon atoms, an alkenylene residue having from 2 to 20,preferably 3 to 20, carbon atoms, an alkynylene residue having from 2 to20, preferably 3 to 20, carbon atoms, cycloalkylidene residue havingfrom 5 to 12 carbon atoms, an arylene residue having 6 to 14 carbonatoms, an aralkylene residue having from 8 to 14 carbon atoms or analiphatic, aromatic or heterocyclic diacyl residue, ##STR11## analiphatic or aromatic dicarbamoyl or dithiocarbamoyl residue, sulphinylor sulphonyl residue or a divalent residue obtained by removing twohydroxyl groups from a disulphonic acid, a phosphorus containing acid ora boric acid.

When n is 3, R₃ is a trivalent residue and is an arenetriyl or anarenetriyl-trialkylene residue, an aliphatic or aromatic triacyl residueor a triacyl residue derived from o-phosphoric, o-phosphorous or o-boricacid; and

when n is 4, R₃ is a tetravalent residue and is an alkane tetraylresidue, or a tetraacyl residue derived from an aliphatic or aromatictetracarboxylic acid or from o-silicic acid;

as well as, when n is 2, 3 or 4, partial ethers, esters and carbamoyloxyand thiocarbamoyloxy compounds related to the fully-reacted compounds offormula I.

When n is 1, R₁ and/or R₃ may be an alkyl residue having from 1 to 20carbon atoms, preferred 1 to 18, examples of this substituent aremethyl, ethyl, n-propyl, n-butyl, sec-butyl, t-butyl, n-hexyl, n-octyl,2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl,n-tetradecyl, n-hexadecyl or n-octadecyl residue and eicosyl. In termsof accessibility and activity however for optimal compatibility withpolyolefines substrates, alkyl substituents R₁ and/or R₃ having from 5to 20, especially 5 to 12 carbon atoms are preferred. A sub-group ofalkyl residues R₁ is that containing from 1 to 4 carbon atoms,preferably methyl.

In those cases in which R₁ and/or R₃ is an alkenyl residue having from 3to 20 carbon atoms, examples of these substituents are allyl, methallyl,3-hexenyl, 4-octenyl, 6-decenyl, 10-undecenyl, and 8-octadecenylresidues, however the preferred substituents in this group are allyl andmethallyl residues.

When the residues R₁ and/or R₃ are alkynyl they may be for examplepropargyl, but-1- and -2-ynyl, pent-1-ynyl, hex-1-ynyl, oct-1-ynyl,dec-1-ynyl, dodec-1-ynyl, tetradec-1-ynyl and octadec-1-ynyl. Thepreferred alkynyl substituents however are propargyl andmethylpropargyl.

When R₁ and/or R₃ is an aralkyl residue, suitable examples are benzyl,β-phenethyl, α-methylbenzyl, α,α-dimethylbenzyl, α-naphthylmethyl andp-methyl-α-methylbenzyl residues. Benzyl is preferred.

A further sub-group of R₁ and/or R₃ substituents is substituted alkylderivatives having the formula: ##STR12## wherein m, R₄, X₁ and X₂ havetheir previous significance, but wherein, however, R₄ is preferablyhydrogen and m is preferably 1.

When X₁ is an hydroxyl residue, examples of this substituents R₁ and/orR₃ are 2-hydroxyethyl, 2- and 3-hydroxypropyl, 3- and 4-hydroxybutyl,4-hydroxypentyl and 2-hydroxy-2-phenyl ethyl, preferably 2-hydroxyethyl,2-hydroxypropyl and 2-hydroxy-2-phenylethyl.

When X₁ and/or X₂ are halogen atoms, examples of R₁ and/or R₃ include2-chloro- and 2-bromo ethyl, 2- and 3-chloro- and 2- and 3-bromopropyl,3- and 4-chorobutyl and 2-chloro-2-phenyl ethyl, preferably2-choroethyl, 2-chloropropyl and 2-chloro-2-phenylethyl.

When X₁ and/or X₂ are cyano groups, R₁ and/or R₃ include cyanomethyl, 1-and 2- cyanobutyl, 4-cyanopentyl, 2-cyano-2-phenylethyl groups,preferably a 2-cyanoethyl group.

When X₂ is a 1,2-epoxy group, R₁ and/or R₃ may be 2,3-epoxy-n-propyl,2,3-epoxy-methylpropyl, but the preferred epoxyalkyl substituent is2,3-epoxy-n-propyl.

When X₁ is --OR₅, --OCOR₅, --OCSR₅, --OCONR₆ R₅, --CSNR₆ R₅, or when X₁and/or X₂ are --COR₅, --COOR₅, --COSR₅, --CONR₆ R₅ and the group R₅ isalkyl, then the alkyl group preferably has from 1 to 12, most preferred1 to 2, carbon atoms; when R₅ is an alkenyl residue, then it preferablycontains 2 to 4 carbons; when R₅ is a cycloalkyl group it preferablycontains 6 carbon atoms; when R₅ is an aryl residue it preferablycontains 6 or 7 carbons; and when R₅ is an aralkyl residue, itpreferably has 7 or 8 carbon atoms.

R₅ and R₆ together with the nitrogen atom to which they are bound canform a 5- or 6-membered ring such as the pyrrolidinyl-, imidazolidinyl-,pyrazolidinyl-, piperidinyl-, piperazinyl- or morpholinyl ring.

Examples of R₁ and/or R₃ within this sub-group are 2-methoxyethyl,2-ethoxyethyl, 2-propoxyethyl, 2-butoxyethyl, 2-methoxypropyl, 2- and3-ethoxypropyl, 2- and 3-n-butoxypropyl, 3- and 4-methoxybutyl, 3- and4-ethoxybutyl, 3- and 4-butoxybutyl, 4-methoxypentyl, 4-ethoxypentyl,4-n-butoxy-pentyl, 2-methoxy-2-phenyl ethyl, 2-ethoxy-2-phenyl ethyl;2-acetoxyethyl, 2-n-propionoxyethyl, 2-benzoyloxy ethyl,2-acetoxypropyl, 2-n-propionoxypropyl, 4-acetoxybutyl,4-n-propionoxybutyl, 4-acetoxypentyl, 4-n-propionoxypentyl,2-phenyl-2-acetoxyethyl, 2-(methylcarbamoyloxy) ethyl,2-(ethylcarbamoyloxy)ethyl, 2-(phenylcarbamoyloxy) ethyl,2-(methylcarbamoyloxy) propyl, 2-(ethylcarbamoyloxy) propyl,2-phenyl-2-(carbamoyloxy) ethyl, 2-(allylthiocarbamoyloxy) ethyl,2-phenyl-2-(methylcarbamoyloxy) ethyl, 2-phenyl-2-(phenylcarbamoyloxy)ethyl, methylcarbonylmethyl, 2-(methyl-carbonyl) ethyl,2-(ethyl-carbonyl) ethyl, 2-(methylcarbonyl) propyl, and2-(methylcarbonyl)-2-phenyl ethyl; methoxycarbonyl methyl,2-(ethoxycarbonyl) ethyl, 2-(methoxycarbonyl)-propyl, and2-(methoxycarbonyl)-2-phenylethyl, 2-(ethylthiocarbonyl) ethyl,2-(methylthiocarbonyl) propyl and 2-(methylthiocarbonyl)-2-phenylethyl;carbamoylmethyl, 2-carbamoylethyl, 2-methylcarbamoylethyl,2-ethylcarbamoylethyl, dimethylcarbamoylmethyl, 2-diethylcarbamoylethyl,thiocarbamoylmethyl, 2-(thiocarbamoyl)ethyl, 2-methylthiocarbamoylethyl,dimethylthiocarbamoylmethyl, 2-(phenylcarbamoyl)ethyl.

When n is 1 and R₁ and/or R₃ is an acyl group -COR₇ wherein R₇ is anunsubstituted aliphatic or substituted aliphatic residue having from 1to 20, preferably 1 to 19, carbon atoms, R₇ may be a methyl, ethyl,propyl, butyl, hexyl, n-octyl, 2-ethylhexyl, n-decyl, n-undecyl,n-tridecyl, n-tetradecyl, n-hexadecyl, n-heptadecyl and eicosyl,chloroethyl, chlorohexyl, methylthioethyl, ethylthioethyl,octylthioethyl, or dodecylthioethyl residue; alkenyl residues R₇ havefrom 2 to 20, preferably 2 to 17, most preferred 2 to 6, carbon atomssuch as vinyl, allyl, methallyl, isobutenyl or hexenyl group; alkynylresidues R₇ have from 2 to 20, preferably 2 to 6, carbon atoms such as apropargyl group; cycloaliphatic residues R₇ have from 5 to 12,preferably 6 to 10, most preferred 6, carbon atoms such as a cyclopentylor cyclohexyl residue; araliphatic residues R₇ have from 7 to 14,preferably 7 to 13, most preferred 7 to 9, carbon atoms such as abenzyl, β-phenylethyl, diphenylmethyl or styryl residue; unsubstitutedaromatic residues R₇ have from 6 to 14, preferably 6 to 10, carbon atomssuch as a phenyl or naphthyl residue, a substituted aromatic residue,substituted by for example alkyl having 1 to 4 carbon atoms such astolyl, p-tertbutylphenyl; and heterocyclic residues R₇ may be a furan orthiophene residue. Examples of compounds wherein R₁ and/or R₃ areunsaturated acyl groups are preferred those wherein only one of R₁ andR₃ denotes an unsaturated acyl group.

Examples of acyl groups R₁ and/or R₃ are formyl, acetyl, propionyl,n-butyryl, hexanoyl, heptanoyl, octanoyl, 2-ethylhexanoyl,2,2,4-trimethylpentanoyl, n-decanoyl, n-dodecanoyl, n-tetradecanoyl,n-hexadecanoyl, n-octadecanoyl, n-eicosoyl, acryloyl, α-methacrylol,crotonoyl, undec-10-enoyl, octadec-9-enoyl, β-methylthiopropionyl,methylthioacetyl, β-octylthiopropionyl, β-dodecylthiopropionyl,cyclopentanoyl, cyclohexanoyl, benzoyl, α- and β-naphthoyl,cyclopentylacetyl, cyclohexylacetyl, phenylacetyl, β-phenylpropionyl,diphenyloctyl, β-phenylacryloyl, o-, m- and p-toluoyl, o-, m- orp-methoxybenzoyl and o-, m- and p-chlorobenzoyl, 2-furoyl and2-picolinoyl.

When n is 1, R₁ and/or R₃ may also be a carbamoyl or thiocarbamoylresidue having the formula: ##STR13## wherein X₃ is -O- or -S-, R₈ ishydrogen or an alkyl residue having from 1 to 4 carbon atoms and R₉ ishydrogen, an alkyl residue having from 1 to 20, preferably 1 to 8,carbon atoms, an alkenyl residue having from 3 to 20 carbon atoms, acycloalkyl residue having from 5 to 12 carbon atoms or an unsubstitutedalkyl, or substituted aryl, for instance, alkyl or halogen-substitutedaryl residue having from 6 to 12, preferably 6 to 10, carbon atoms.Examples of suitable residues within this group are carbamoyl,N-methylcarbamoyl, N-ethyl-carbamoyl, N-n-propylcarbamoyl,N-isopropylcarbamoyl, N-n-butylcarbamoyl, N-n-pentylcarbamoyl,N-n-octylcarbamoyl, N-n-decylcarbamoyl, N-n-dodecylcarbamoyl,N-n-octadecyl, N-n-eicosylcarbamoyl, N-allylcarbamoyl,N-methallylcarbamoyl, N-undecenylcarbamoyl, N-cyclopentylcarbamoyl,N-cyclohexylcarbamoyl, N-methylcyclohexylcarbamoyl,N-cyclododecylcarbamoyl, N-(1- and 2-perhydronaphthyl)carbamoyl,N-adamantylcarbamoyl, N-cyclopentylmethylcarbamoyl, N-benzylcarbamoyl,N-(β-phenethyl)carbamoyl, N-(1- and 2-naphthylmethyl)carbamoyl,N-phenylcarbamoyl, N-(o-, m- and p-tolyl)carbamoyl, N-(2,4- and2,6-xylyl)carbamoyl, N-(α-and β-naphthyl)carbamoyl,N,N-dimethylcarbamoyl, N-methyl, N-ethylcarbamoyl, N,N-diethylcarbaroylN,N-diisopropylcarbamoyl, N,N-di-n-propylcarbamoyl,N,N-di-n-butyl-carbamoyl and N,N-di-isobuty-carbamoyl residues as wellas the corresponding thiocarbamoyl residues.

When R₂ is an alkyl residue it is for example methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl, t-butyl, preferably methyl, as alkenylresidue R₂ is for example allyl, methallyl, 3-hexenyl, 4-octenyl,6-decenyl, 10-undecenyl or 8-octadecenyl, preferably allyl or methallyland as alkynyl residue for example propargyl, but-1- and -2-ynyl,penta-1-ynyl, hex-1-ynyl, oct-1-ynyl, dec-1-ynyl, dodec-1-ynyl,tetradec-1-ynyl and octadec-1-ynyl, preferably propargyl, R₂ ascycloalkyl is for example cyclopentyl, cyclohexyl, cyclooctyl,cyclododecyl, preferably cyclohexyl as aryl residue R₂ is for examplephenyl, p-tolyl, t-butylphenyl, naphthyl, preferably phenyl or p-tolyland as aralkyl residue it is for example benzyl, alpha-methylbenzyl,p,alphadimethylbenzyl, preferably benzyl.

When n is 1

R₃ may be the same as R₁. If R₃ is alkyl it is preferably an alkyl grouphaving from 3 to 18 carbon atoms.

When R₃ represents an aryl residue it is for example an aromatic residuehaving 6 to 20 carbon atoms, preferably an aryl residue having 6 to 12carbon atoms, most preferred phenyl.

When n is 2

R₃ is, for example an alkylene residue having from 1 to 20, preferably 2to 6, carbon atoms such as methylene, ethylene, trimethylene,tetramethylene or hexamethylene residue. Alkenylene residues R₃preferably contain 3 to 20, most preferred 3 or 4 carbons, and may be,for instance a 1,3-propen-ene or 1,4-buten-2-ene residue. Alkynyleneresidues R₃ preferably contain 3 to 20, most preferred 4 carbon atomsand may be, for instance a 1:4 but-2-ynylene residue. When R₃ is acycloalkylidene residue, it preferably contains 7 or 8 carbon atoms, forinstance a cyclohexyldimethylene residue.

When R₃ is arylene it has preferably 6 to 12 carbon atoms and it may befor example 1,3-phenylene, or 4,4'-diphenylene.

When R₃ is aralkylene it may be for example α,α-pxylylene.

Diacyl residues R₃ include those derived from an aliphatic, aromatic orheterocyclic dicarboxylic acid. Examples of aliphatic dicarboxylic acidsare those having from 2 to 20, preferably alkan dicarboxylic acidshaving 6 to 10 carbon atoms such as malonic, succinic, glutaric, adipic,pimelic, suberic, azelaic, sebacic, 1,12-dodecanedioic,1,18-octadecanedioic, 1,20 -docosanedioic acid and N-methyliminodiaceticacid. Examples of aromatic diacyl residues are those derived fromphthalic, isophthalic and terephthalic acids, each optionallyring-substitued, for instance by halogen, an alkyl or alkoxy group eachhaving from 1 to 20 carbon atoms, a hydroxy or tertiary amino group.

Examples of heterocyclic dicarboxylic acids are 2,5-thiophenedicarboxylic acid or 2,5-furandicarboxylic acid.

R₃ is for example an aliphatic or aromatic dicarbamoyl residue such as adivalent alkyl dicarbamoyl residue for example the divalent residue ofbutan-1,4-dicarbamoyl or hexan-1,6-dicarbamoyl or such as a divalentaryl dicarbamoyl residue such as the divalent residue ofphenyl-1,4-dicarbamoyl. R₃ is for example an aliphatic or aromaticdithicarbamoyl residue such as a divalent alkyl dithiocarbamoyl residuefor example the divalent residue of butan-1,4-dithiocarbamoyl orhexan-1,6-dithiocarbamoyl or such as an divalent aryl dithiocarbamoylresidue such as the divalent residue of phenyl1,4-dithiocarbamoyl.

When n is 3

R₃ is, for instance, a triacyl group derived from an aliphatictricarboxylic acid such as nitrilotriacetic acid, tricarballylic acid,from an aromatic tricarboxylic acid such as benzene tricarboxylic acidor from an inorganic acid such as o-phosphorous, o-phosphoric or o-boricacid, or oxyacids, for example, benzene-1,3,5-trisulphonic acid.

When n is 4

R₃ is, for instance, a tetracyl group derived from a tetracarboxylicacid, such as ethylene diamine, tetracarboxylic acid, from thetetracarboxylic acids described in British Patent Specification No.1080335, 1,2,4,5,-benzene tetracarboxylic acid or from o-silicic acid.

R₃ preferably represents an acyl or an N- substituted carbamoyl, analkylene group, a substituted alkylene or an aralkyl group.

R₁ preferably represents an alkyl, alkenyl, or substituted alkyl groupsuch as hydroxyalky, alkylcarbonyloxy or aralkyl group.

Examples of compounds of the present invention are:

Examples where n = 1

4-Methoxy-1,2,2,6,6-pentamethylpiperidine

4-n-Butoxy-1,2,2,6,6-pentamethylpiperidine

4-n-Dodecyloxy-1,2,2,6,6-pentamethylpiperidine

4-n-Octadecyloxy-1,2,2,6,6-pentamethylpiperidine

4-(2'-Cyanoethoxy)-1,2,2,6,6-pentamethylpiperidine

4-(2'-Hydroxyethoxy)-1,2,2,6,6-pentamethylpiperidine

1-n-Propyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-n-Propyl-4-n-dodecyloxy-2,2,6,6-tetramethylpiperidine

1-n-Propyl-4-n-octadecyloxy-2,2,6,6-tetramethylpiperidine

1-sec-Butyl-4-n-dodecyloxy-2,2,6,6-tetramethylpiperidine

1-n-Octyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-n-Dodecyl-4-n-dodecyloxy-2,2,6,6-tetramethylpiperidine

1-n-Octadecyl-4-methoxy-2,2,6,6-tetramethylpiperidne

1-n-Octadecyl-4-n-octadecyloxy-2,2,6,6-tetramethylpiperidine

1-n-Eicosyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Allyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Allyl-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-(1'-Undec-10'-enyl)-4-n-butoxy-2,2,6,6-tetramethylpiperidine

1-(1'-Undec-10'-enyl)-4-(1'-undec-10'-enyloxy)-2,2,6,6-tetramethylpiperidine

1-Oleyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Oleyl-4-oleyloxy-2,2,6,6-tetramethylpiperidine

1-Propargyl-4-ethoxy-2,2,6,6-tetramethylpiperidine

1-Propargyl-4-proparglyloxy-2,2,6,6-tetramethylpiperidine

1 Benzyl-4-n-dodecyloxy-2,2,6,6-tetramethylpiperidine

1-Benzyl-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-Benzyl-4-propargyloxy-2,2,6,6-tetramethylpiperidine

1-Benzyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxyethyl)-4-methoxy-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxypropyl)-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxyethyl)-4-propargyloxy-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxypropyl)-4-benzyloxy2,2,6,6-tetramethylpiperidine

1(2'-Hydroxyethyl)-4-(2'-hydroxyethoxy)-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxypropyl)-4-(2'-hydroxypropoxy)-2,2,6,6-tetramethylpiperidine

1-(2'-Hydroxy-2'-phenylethyl)-4-n-butoxy-2,2,6,6-tetramethylpiperidine

1(2'-Hydroxy-2'-phenylethyl)-4-(2'-hydroxy-2'-phenylethoxy)-2,2,6,6-tetramethylpiperidine

1-(2'-Chloroethyl)-4-n-docecyloxy-2,2,6,6-methylpiperidine

1-(2'-Chloropropyl)-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1(2'-Bromoethyl(-4-(2'-bromoethoxy)-2,2,6,6-tetramethylpiperidine

1(2'-Chloro-2'-phenylethyl)-4-n-octyloxy-2,2,6,6-tetramethylpipridine

1(2'-Cyanoethyl)-4-phenoxy-2,2,6,6-tetramethylpiperidine

1(2'-Cyanoethyl)-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1(2'-Cyanoethyl)-4-(2'-cyanoethoxy)-2,2,6,6-tetramethylpiperidine

1(2'-Cyanopropyl)-4-methoxy-2,2,6,6-tetramethylpiperidine

1(2',3'-epoxypropyl)-4-n-butoxy-2,2,6,6-tetramethylpiperidine

1(2',3'-epoxypropyl)-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1(2',3'-epoxypropyl)-4-(2',3'-epoxypropoxy)-2,2,6,6-tetramethylpiperidine

1(2'-methoxyethyl)-4-ethoxy-2,2,6,6-tetramethylpiperidine

1(2'methoxyethyl)-4-(2'methoxyethoxy)-2,2,6,6tetramethylpiperidine

1-(2'-ethoxypropyl)-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-(2'-ethoxy-2'phenylethyl)-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1(2'acetoxyethyl)-4-n-butoxy-2,2,6,6-tetramethylpiperidine

1(2'-benzoyloxyethyl)-4-(2'-benzoyloxyethoxy)-2,2,6,6tetramethylpiperidine

1-(2'-propionoxypropyl)-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-[2'-(methylcarbamoyloxy)ethyl]-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1-[2'-(methylcarbamoyloxy)ethyl]-4-[2'-(methylcarbamoyloxy)ethoxy]2,2,6,6-tetramethylpiperidine

1-[2'-(Phenylcarbamoyloxy)ethyl]-4-[2'-cyanoethoxy)]-2,2,6,6-tetramethylpiperidine

1-[2'-(ethylthiocarbamoyloxy)ethyl]-4-[2'-ethylthiocarbamoyloxy)ethoxy]-2,2,6,6-tetramethylpiperidine

1-Methylcarbonylmethyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-[(methylcarbonyl)ethyl]-4-n-octyloxy-2,2,6,6-tetramethylpiperidine

1-Methylcarbonylmethyl-4-methylcarbonylmethoxy-2,2,6,6-tetramethylpiperidine

1-(2'-methoxycarbonylethyl)-4-(2'-methoxycarbonylethoxy)-2,2,6,6-tetramethylpiperidine

1-(2'-methoxycarbonylethyl)-4-ethoxy-2,2,6,6-tetramethylpiperidine

1-[2'-(ethoxycarbonyl)ethyl]-4-(2'-hydroxyethoxy)-2,2,6,6-tetramethylpiperidine

1-[2'-(thioethoxycarbonyl)ethyl]-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Carbamoylmethyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1-(2'-Carbamoylethyl-4-dodecoxy-2,2,6,6-tetramethylpiperidine

1-[2'-(Methylcarbamoyl)ethyl]-4-[2'-methylcarbamoylethoxy]-2,2,6,6-tetramethylpiperidine

1-[2'-(Diethylcarbamoyl)ethyl]-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Thiocarbamoylmethyl-4-allyloxy-2,2,6,6-tetramethylpiperidine

1-(Dimethylthiocarbamoyl)methyl-4-benzloxy-2,2,6,6-tetramethylpiperidine

1-Acetyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1-Lauroyl-4-(2'-hydroxyethoxy)-2,2,6,6-tetramethylpiperidine

1-Stearoyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Benzoyl-4-n-butoxy-2,2,6,6-tetramethylpiperidine

1-Carbamoyl-4-n-octadecyloxy-2,2,6,6-tetramethylpiperidine

1-Methylcarbamoyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine

1-Phenylcarbamoyl-4-(2'-hydroxyethoxy)-2,2,6,6-tetramethylpiperidine

1-Phenylthiocarbamoyl-4-(cyclohexyloxy)-2,2,6,6-tetramethylpiperidine

1-Dimethylcarbamoyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1-Methylthiocarbamoyl-4-n-octyloxy-2,2,6,6-tetramethylpiperidine

1-Phenylthiocarbamoyl-4-methoxy-2,2,6,6-tetramethylpiperidine

1,2,2,6,6-Pentamethylpiperidinyl-4-formate

1,2,2,6,6-Pentamethylpiperidinyl-4-acetate

1,2,2,6,6-Pentamethylpiperidinyl-4-isobutyrate

1,2,2,6,6-Pentamethylpiperidinyl-4-n-octanoate

1,2,2,6,6-Pentamethylpiperidinyl-4-pivalate

1,2,2,6,6-Pentamethylpiperidinyl-4-stearate

1,2,2,6,6-Pentamethylpiperidinyl-4-eicosanoate

1,2,2,6,6-Pentamethylpiperidinyl-4-(2'-ethylhexanoate)

1,2,2,6,6-Pentamethylpiperidinyl-4-acrylate

1,2,2,6,6-Pentamethylpiperidinyl-4-oleate

1,2,2,6,6-Pentamethylpiperidinyl-4-cyclohexanecarboxylate

1,2,2,6,6-Pentamethylpiperidinyl-4-adamantane-1-carboxylate

1,2,2,6,6-Pentamethylpiperidinyl-4-benzoate

1,2,2,6,6-Pentamethylpiperidinyl-4-p-toluate

1,2,2,6,6-Pentamethylpiperidinyl-4-p-t-butylbenzoate

1,2,2,6,6-Pentamethylpiperidinyl-4-p-methoxybenzoate

1,2,2,6,6-pentamethylpiperidinyl-4-o-chloro-benzoate

1,2,2,6,6-Pentamethylpiperidinyl-4-p-chloro-benzoate

1,2,2,6,6-Pentamethylpiperidinyl-4-α-naphthoate

1,2,2,6,6-Pentamethylpiperidinyl-4-phenylacetate

1,2,2,6,6-Pentamethylpiperidinyl-4-(1'-naphthylacetate)

1,2,2,6,6-Pentamethylpiperidinyl-4-cinnamate

1,2,2,6,6-Pentamethylpiperidinyl-4-diphenylacetate

1,2,2,6,6-Pentamethylpiperidinyl-4-n-dodecylthioacetate

1,2,2,6,6-Pentamethylpiperidinyl-4-(furan-2'-carboxylate)

1,2,2,6,6-Pentamethylpiperidinyl-dimethyl trimesate

1-n-Propyl-2,2,6,6-tetramethylpiperidinyl-acetate

1-n-Propyl-2,2,6,6-tetramethylpiperidinyl-4-octanoate

1-n-Propyl-2,2,6,6-tetramethylpiperidinyl-4-stearate

1-n-Octyl-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-n-Dodecyl-2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-n-Dodecyl-2,2,6,6-tetramethylpiperidinyl-4-p-chlorobenzoate

1-n-Octadecyl-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-Allyl-2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-Allyl-2,2,6,6-tetramethylpiperidinyl-4-cyclohexanecarboxylate

1-Allyl-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-α-Methallyl-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-Oleyl-2,2,6,6-tetramethylpiperidinyl-4-cyclohexane-carboxylate

1-Propargyl-2,2,6,6-tetramethylpiperidinyl-4-p-methoxybenzoate

1-Benzyl-2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-Benzyl-2,2,6,6-tetramethylpiperidinyl-4-(2'-ethylhexanoate)

1-Benzyl-2,2,6,6-tetramethylpiperidinyl-4-stearate

1-Benzyl-2,2,6,6-tetramethylpiperidinol-4-benzoate

1-(2'-Hydroxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-(2'-Hydroxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-laurate

1-(2'-Hydroxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-stearate

1-(2'-Hydroxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-(2'-Hydroxypropyl)-2,2,6,6-tetramethylpiperidinyl-4-oleate

1-(2'-Hydroxy-2'-phenylethyl)-2,2,6,6-tetramethylpiperidinyl-4-phenylacetate

1-(2'-Chloroethyl)-2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-(2'-Bromopropyl)-2,2,6,6-tetramethylpiperidinyl-4-cyclohexane-carboxylate

1-(2'-Chloro-2'-phenylethyl)-2,2,6,6-tetramethylpiperidinyl-4-p-methoxybenzoate

1-(2'-Cyanoethyl)-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-(2'-Cyanopropyl)-2,2,6,6-tetramethylpiperidinyl-4-p-chlorobenzoate

1-(2',3'-epoxypropyl)-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-(2'-ethoxypropyl)-2,2,6,6-tetramethylpiperidinyl-4-(2'-ethylhexanoate)

1-(2'-ethoxy-2'-phenylethyl)-2,2,6,6-tetramethylpiperidinyl-4-diphenylacetate

1-(2'-acetoxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-laurate

1-[2'-(methylcarbamoyloxy)ethyl-9-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-[2'-(phenylcarbamoyloxy)ethyl]-2,2,6,6-tetramethylpiperidinyl-4-isobutyrate

1-[2'-(ethylthiocarbamoyloxy)ethyl]-2,2,6,6-tetramethylpiperidinyl-4-pivalate

1-Methylcarbonylmethyl-2,2,6,6-tetramethylpiperidinyl-4-phenylacetate

1-[2'-(methylcarbonyl)ethyl]-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-Ethoxycarbonylmethyl-2,2,6,6-tetramethylpiperidinyl-4-p-methoxybenzoate

1-[2'-(Methoxycarbonyl)ethyl]-2,2,6,6-tetramethylpiperidinyl-4-p-toluate

1-Carbamoylmethyl-2,2,6,6-tetramethylpiperidinyl-4-p-methoxybenzoate

1-(2'-Carbamoylethyl)-2,2,6,6-tetramethylpiperidinyl-4-stearate

1-[2'-(methylcarbamoyl)ethyl]-2,2,6,6-tetramethylpiperidinyl-4-octanoate

1-(Dimethylthiocarbamoyl)methyl-2,2,6,6-tetramethylpiperidinyl-4-isobutyrate

1-Acetyl-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-Acetyl-2,2,6,6-tetramethylpiperidinyl-4-(2'-ethylhexanoate)

1-Acetyl-2,2,6,6-tetramethylpiperidinyl-4-stearate

1-Isobutyrl- 2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-Lauroyl-2,2,6,6-tetramethylpiperidinyl-4-eicosanoate

1-Stearoyl-2,2,6,6-tetramethylpiperidinyl-4-acetate

1-Benzoyl-2,2,6,6-tetramethylpiperidinyl-4-benzoate

1-Carbamoyl-2,2,6,6-tetramethylpiperidinyl-4-(1'-naphthyl-acetate)

1-Methylcarbamoyl-2,2,6,6-tetramethylpiperidinyl-4-n-octanoate

1-Phenylcarbamoyl-2,2,6,6-tetramethylpiperidinyl-4-phenylacetate

1-Dimethylcarbamoyl-2,2,6,6-tetramethylpiperidinyl-4-laurate

1-Phenylthiocarbamoyl-2,2,6,6-tetramethylpiperidinyl-4-p-t-butylbenzoate

4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-methylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-dimethylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-isopropylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-t-butylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-n-hexylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-[2'-ethylhexylcarbamoyloxy]-1,2,2,6,6-pentamethylpiperidine

4-n-dodecylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-n-octadecylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-allylcarbamoyloxy-1,2,2,6,6 -pentamethylpiperidine

4-oleylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-cyclohexylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-[3'-methylcyclohexylcarbamoyloxy]-1,2,2,6,6-pentamethylpiperidine

4-[4'-t-butylcyclohexylcarbamoyloxy]-1,2,2,6,6-pentamethylpiperidine

4-cyclohexylmethylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-benzylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-phenylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-phenylthiocarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-m-tolylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-p-tolylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-p-chlorophenylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-p-t-butylphenylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-α-naphthylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine

4-cyclohexylcarbamoyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-n-propyl-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-secbutyl-2,2,6,6-tetramethylpiperidine

4-n-octadecylcarbamoyloxy-1-n-butyl-2,2,6,6-tetramethylpiperidine

4-Methylcarbamoyloxy-1-n-octyl-2,2,6,6-tetramethylpiperidine

4-Methylcarbamoyloxy-1-n-octadecyl-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyloxy-1-allyl-2,2,6,6-tetramethylpiperidine

4-tolylcarbamoyloxy-1-oleyl-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-propargyl-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyloxy- 1-benzyl-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-(2'-hydroxyethyl)-2,2,6,6-tetramethylpiperidine

4-cyclohexylcarbamoyloxy-1-(2'-chloropropyl)-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyloxy-1-(2'-hydroxy-2'-phenylethyl)-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-(2',3'-epoxypropyl)-2,2,6,6-tetramethylpiperidine

4-carbamoyloxy-1-(2'-methoxyethyl)-2,2,6,6-tetramethylpiperidine

4-dimethylcarbamoyloxy-1-(2'-acetoxyethyl)-2,2,6,6-tetramethylpiperidine

4-n-hexylcarbamoyloxy-1-[2'-(methylcarbamoyloxy)ethyl]-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-methylcarbonylmethyl-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyl-1-(2'-methylcarbonylethyl)-2,2,6,6-tetramethylpiperidine

4-benzylcarbamoyloxy-1-carbamoylmethyl-2,2,6,6-tetramethylpiperidine

4-n-dodecylcarbamoyloxy-1-(2'-carbamoylethyl)-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-(2'-thiocarbamoylethyl)-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-acetyl-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyloxy-1-stearoyl-2,2,6,6-tetramethylpiperidine

4-methylthiocarbamoyloxy-1-lauroyl-2,2,6,6-tetramethylpiperidine

4-[2'-ethylhexylcarbamoyl]-1-benzoyl-2,2,6,6-tetramethylpiperidine

4-carbamoyloxy-1-carbamoyl-2,2,6,6-tetramethylpiperidine

4-methylcarbamoyloxy-1-methylcarbamoyl-2,2,6,6-tetramethylpiperidine

4-phenylcarbamoyloxy-1-phenylcarbamoyl-2,2,6,6-tetramethylpiperidine

4-methylthiocarbamoyloxy-1-methylthiocarbamoyl-2,2,6,6-tetramethylpiperidine

4-phenylthiocarbamoyloxy-1-phenylthiocarbamoyl-2,2,6,6-tetramethylpiperidine

4-dimethylcarbamoyloxy-1-dimethylcarbamoyl-2,2,6,6-tetramethylpiperidine

4-stearyloxy-1,2,2,4,6,6-hexamethylpiperidine

4-phenyl-1,2,2,6,6-pentamethyl-piperidinyl-4-n-octanoate

Examples where n = 2

1,2-Bis(1',2',2',6',6'-pentamethyl-4'-piperidyloxy)ethane

1,4-Bis(1'-n-propyl-2',2',6',6'-tetramethyl-4'-piperidyloxy) butene

1,6-Bis(1'-n-octadecyl-2',2',6',6'-tetramethyl-4'-piperdidyloxy)hexane

1,4-Bis(1'-allyl-2',2',6',6'-tetramethyl-4'-piperidyloxy) cyclohexane

1,4-Bis(1'-propargyl-2',2',6',6'-tetramethyl-4-piperidyloxy) but-2-ene

α,α-Bis(1-benzyl-2,2,6,6-tetramethyl-4-piperidyloxy)p-xylene

1,3-Bis[1'-(2"-hydroxyethyl)-2',2',6',6'-tetramethyl-4'-piperidyloxy]benzene

1,2-Bis[1'-(2"-cyanoethyl)-2',2',6',6'-tetramethyl-4'-piperidyloxy]ethane

1,4-Bis(1'-acetyl-2',2',6',6'-tetramethyl-4'-piperidyloxy) but-2-yne

4,4-Bis(1"-methylcarbamoyl-2",2",6",6"-tetramethyl-4"-piperidyloxy)diphenylmethane

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)carbonate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)oxalate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)malonate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)adipate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)fumarate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)isophthalate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)cyclohexane 1',4'-dicarboxylate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)thiodipropionate

Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)methyltrimesate

Bis(1-n-propyl-2,2,6,6-tetramethyl-4-piperidinyl)adipate

Bis(1-secbutyl-2,2,6,6-tetramethyl-4-piperidinyl)succinate

Bis(1-n-octyl-2,2,6,6-tetramethyl-4-piperidinyl)sebacate

Bis-(1-n-dodecyl-2,2,6,6-tetramethyl-4-piperidinyl)adipate

Bis(1-n-octadecyl-2,2,6,6-tetramethyl-4-piperidinyl)sebacate

Bis(1-allyl-2,2,6,6-tetramethyl-4-piperidinyl)adipate

Bis(1-allyl-2,2,6,6-tetramethyl-4-piperidinyl)thiophene-2',5'-dicarboxylate

Bis(1-oleyl-2,2,6,6-tetramethyl-4-piperidinyl)thiodipropionate

Bis(1-propargyl-2,2,6,6-tetramethyl-4-piperidinyl)sebacate

Bis(1-benzyl-2,2,6,6-tetramethyl-4-piperidinyl)sebacate

Bis[ 1-(2'-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl]adipate

Bis[1-(2'-chloropropyl)-2,2,6,6-tetramethyl-4-piperidinyl]succinate

Bis[1-(2'-cyanoethyl)-2,2,6,6-tetramethyl-4-piperidinyl]sebacate

Bis[1-(2',3'-epoxypropyl)-2,2,6,6-tetramethyl-4-piperidinyl]azelate

Bis[1-(2'-methoxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl]pimelate

Bis[1-(2'-acetoxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl]glutarate

Bis[1-(2'-methylcarbamoyloxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl]malonate

Bis[1-(methylcarbonylmethyl)-2,2,6,6-tetramethyl-4-piperidinyl]terephthalate

Bis[1-carbamoylmethyl-2,2,6,6-tetramethyl-4-piperidinyl]cyclohexane-1',4'-dicarboxylate

Bis[1-(methylcarbamoylethyl)-2,2,6,6-tetramethyl-4-piperidinyl]thiodipropionate

Bis[1-acetyl-2,2,6,6-tetramethyl-4-piperidinyl]sebacate

Bis[1-stearoyl-2,2,6,6-tetramethyl-4-piperidinyl]succinate

Bis[1-Benzoyl-2,2,6,6-tetramethyl-4-piperidinyl]dodecandioate

Bis[1-methylcarbamoyl-2,2,6,6-tetramethylpiperidinyl]adipate

Bis[1-phenylthiocarbamoyl-2,2,6,6-tetramethylpiperidinyl]isophthalate

ethane-1',2'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

hexane-1',6'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

2',4',4'-trimethylhexane-1',6'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

cyclohexane-1',3'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

benzene-1',4'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

toluene-2',4'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

toluene-2',4'-bis[4-thiocarbamoyloxy-1,2,2,6,6-pentamethylpiperidine]naphthalene-1',5'-bis[4-carbamoyloxy-1,2,2,6,6-pentamethyl-piperidine]

diphenylmethane-4',4"-bis[4-carbamoyloxy-1,2,2,6,6-pentamethylpiperidine]

toluene-2',4'-bis[4-carbamoyloxy-1-n-propyl-2,2,6,6-tetramethylpiperidine]

hexane-1',6'-bis[4-carbamoyloxy-1-n-butyl-2,2,6,6-tetramethyl-piperidine]

Hexane-1',6'-bis[4-carbamoyloxy-1-n-octyl-2,2,6,6-2',4',-trimethylhexane-1',6'-bis[4-carbamoyloxy-1-n-octadecyl2,2,6,6-tetramethylpiperidine]

Cyclohexane-1',4'-bis[4-carbamoyloxy-1-allyl-2,2,6,6-tetramethylpiperidine]

2',4',4'-trimethylhexane-1',6'-bis[4-carbamoyloxy-1-allyl-2,2,6,6-tetramethylpiperidine]

Benzene-1',4'-bis[4-carbamoyloxy-1-propargyl-2,2,6,6-tetramethylpiperidine]

toluene-2',4'-bis[4-carbamoyloxy-1-benzyl-2,2,6,6-tetramethylpiperidine]

Toluene-2",4"-bis[4-carbamoyloxy-1-(2'-hydrocyethyl)-2,2,6,6-tetramethylpiperidine]

Diphenylmethane-4',4"-bis[4-carbamoyloxy-1-(2'-cyanoethyl)-2,2,6,6-tetramethylpiperidine

Toluene-2",4"-bis[4-carbamoyloxy-1-(2"-acetoxyethyl)-2,2,6,6-tetramethylpiperidine]

Ethane-1',2'-bis[4-carbamoyloxy-1-methylcarbonylmethyl-2,2,6,6-tetramethylpiperidine]

Hexane-1",6"-bis[4-carbamoyloxy-1-(2'-methylcarbamoylethyl)-2,2,6,6-tetramethylpiperidine]

Naphthalene-1',5'-bis[4-carbamoyloxy-1-acetyl-2,2,6,6-tetramethylpiperidine]

2',4',4'-trimethylhexane-1',6'-[4-carbamoyloxy-1-stearoyl-2,2,6,6-tetramethylpiperidine]

Hexane-1',6'-bis[4-carbamoyloxy-1-methylcarbamoyl-2,2,6,6-tetramethylpiperidine]

Bis[1,2,2,6,6,-pentamethyl-4-piperidinyl]ether

Examples where n = 3

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)nitrilotriacetate

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)tricarballylate

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)trimesate

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)trimellitate

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)phosphite

Tris(1,2,2,6,6-pentamethyl-4-piperidinyl)phosphate

Tris(1,2,2,6,6,-pentamethyl-4-piperidinyl)borate

Tris(1-n-octadecyl-2,2,6,6-tetramethyl-4-piperidinyl)trimesate

Tris(1-allyl-2,2,6,6-tetramethyl-4-piperidinyl)phosphite

Tris(1-propargyl-2,2,6,6-tetramethyl-4-piperidinyl)borate

Tris(1-benzyl-2,2,6,6-tetramethyl-4-piperidinyl)trimellitate

Tris[1-(2'-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl] trimesate

Tris[1-(2'-cyanoethyl)-2,2,6,6-tetramethyl-4-piperidinyl] phosphite

Tris[1-acetyl-2,2,6,6-tetramethyl-4-piperidinyl)borate

Tris[1-methylcarbamoyl-2,2,6,6-tetramethyl-4-piperidinyl]trimesate

Examples where n = 4

Tetrakis(1,2,2,6,6,-pentamethyl-4-piperidinyl)ethylenediaminetetracarboxylate

Tetrakis(1,2,2,6,6-pentamethyl-4-piperidinyl)pyromellitate

Tetrakis(1,2,2,6,6-pentamethyl-4-piperidinyl)-o-silicate

Tetrakis(1-n-octyl-2,2,6,6-tetramethyl-4-piperidinyl)-pyromellitate

Tetrakis(1-allyl-2,2,6,6-tetramethyl-4-piperidinyl)pyromellitate

Tetrakis(1-propargyl-2,2,6,6-tetramethyl-4-piperidinyl)-o-silicate

Tetrakis(1-benzyl-2,2,6,6-tetraethyl-4-piperidinyl) ethylenediaminetetracarboxylate

Tetrakis[1-(2'-hydroxypropyl)-2,2,6,6-tetramethyl-4-piperidinyl]-o-silicate

Tetrakis[1-stearoyl-2,2,6,6-tetramethyl-4-piperidinyl]-pyromellitate

Tetrakis[1-phenylcarbamoyl-2,2,6,6-tetramethyl-4-piperidinyl]-o-silicate

The invention also includes salts of the compounds of Formula I, forinstance salts of inorganic acids such as phosphates, carbonates,sulphates and chlorides and salts of organic acids such as acetates,stearates, maleates, citrates, tartrates, oxalates, benzoates andsubstituted carbamic acids.

Examples of salts are

4-n-butoxy-1,2,2,6,6-pentamethylpiperidine dihydrogen phosphate

4-n-dodecyloxy-1,2,2,6,6-pentamethylpiperidine hydrochloride

bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate sulphate

1,2,2,6,6-pentamethylpiperidinyl-4-beta-(3',5'-di-t-butyl-4'hydroxyphenyl)propionate.bicarbonate

4-methylcarbamoyloxy-1,2,2,6,6,-pentamethylpiperidine.acetate

1,6-bis(4'carbamoyloxy-1',2',2', 6',6'-pentamethylpiperidinehexane.stearate

4-phenyl carbamoyloxy-1,2,2,6,6-pentamethylpiperidine, benzoate

1,2,2,6,6-pentamethylpiperidinyl-4-n-octanoate3',5'-di-t-butyl-4'-hydroxybenzoate

1,4-bis(1',2',2'6',6'-pentamethyl-4'-piperidyloxy)butane hydrogenoxalate

4-(2'-cyanoethoxy)-1,2,2,6,6-pentamethylpiperidine hydrogen maleate

4-stearylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine.citrate

1-(2'-hydroxyethyl)-2,2,6,6,-tetramethylpiperidinyl-4-n-octanoate.tartrate

1,2,2,6,6-pentamethylpiperidinyl-4-benzoate,dibutyl carbamate.

R₁ or R₃ can be represented by a monovalent, divalent or trivalent groupobtained by removing 1 to 3 hydroxyl groups from a sulphonic acid, asulphinic acid, a disulphonic acid, a phosphorus containing acid, suchas o-phosphoric or o-phosphorous acid or boric acid. The following listshows compounds with acid radicals for R₃. However, the same radicalsare also examples for R₁.

a. when n is 1

1,2,2,6,6-pentamethylpiperidinyl-4-benzene sulphinate

1,2,2,6,6-pentamethylpiperidinyl-4-benzene sulphonate

1,2,2,6,6-pentamethylpiperidinyl-4-methyl sulphate

1,2,2,6,6-pentamethylpiperidinyl-4-dimethylborate

1,2,2,6,6-pentamethylpiperidinyl-4-phenyl phosphonate

1,2,2,6,6-pentamethylpiperidinyl-4-dimethyl phosphite

1,2,2,6,6-pentamethylpiperidinyl-4-diphenyl phosphate

b. when n is 2

bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sulphatebis(1,2,2,6,6-pentamethyl-4-piperidinyl)phosphatebis(1,2,2,6,6,-pentamethyl-4-piperidinyl)phenyl phosphatebis(1,2,2,6,6,-pentamethyl-4-piperidinyl)benzene-1,3-disulphinate

c. when n is 3

tris(1,2,2,6,6-pentamethyl-4-piperidinyl)-benzene-1,3,5-trisulphonate

tris(1,2,2,6,6-pentamethyl-4-piperidinyl)-benzene-1,3,5-trisulphinate.

A preferred sub-group of compounds of formula I are those compoundshaving the formula: ##STR14## and their salts, wherein Y is an alkylgroup having from 1 to 20, preferably 1 to 4, carbon atoms, alkenylhaving from 3 to 20 carbon atoms or an aralkyl residue, preferablyhaving from 7 to 9 carbon atoms, and

n₁ is 1 or 2;

when n₁ is 1, R is hydrogen or a monovalent aliphatic residue havingfrom 1 to 20, preferably 6 to 20 carbon atoms, a monovalent alicyclicresidue having from 5 to 12 carbon atoms, or a monovalent aromaticresidue having from 6 to 20 carbon atoms; or ##STR15## and when n₁ is 2,R is a divalent aliphatic residue having from 1 to 20, preferably 4 to20 carbon atoms, a divalent alicyclic residue having from 5 to 12 carbonatoms or a divalent aromatic residue having from 6 to 14 carbon atoms.Two sub-groups of the compounds of the formula Ia are those having as Yalkyl from 1 to 4 carbon atoms and alkyl having 5 to 20 carbon atoms.

Examples of substituents Y are methyl, ethyl, n-propyl, isopropyl,n-butyl, sec.butyl, n-hexyl, n-octyl, n-dodecyl, n-octadecyl, eicosyl,allyl, methallyl, oleyl, benzyl, α-methylbenzyl, p-methylbenzyl andp-methyl-αmethylbenzyl, However, it is particularly preferred that Y ismethyl.

When n₁ is 1, R can be hydrogen, methyl, ethyl, n-propyl, isopropyl,n-butyl, sec.butyl, t-butyl, n-pentyl, 2-ethyl-propyl, 2-methylbutyl,n-hexyl, 2-methylpentyl, n-heptyl, 2-ethylpentyl, n-octyl,2,2,4-trimethylpentyl, n-decyl, n-undecyl, n-tridecyl, n-pentadecyl,n-heptadecyl, eicosyl, vinyl, α- or β-methylvinyl, dec-9-enyl,heptadec-8-enyl, β-methylthioethyl, β-octylthioethyl,β-dodecylthioethyl, cyclopentyl, cyclohexyl, cyclohex-3-enyl,methylcyclohexyl, t-butylcyclohexyl, cyclododecyl, 1- or2perhydronaphthyl, adamantyl, cyclopentylmethyl, cyclohexylmethyl,β-cyclohexylethyl, 1- or 2-(perhydronaphthyl)methyl, β-[1- or2-perhydronaphthyl]ethyl, benzyl, βphenylethyl, β-phenylvinyl, 1- or2-naphthylmethyl, β-[1- or 2-naphthyl]ethyl, phenyl, o-, m- or p-tolyl,o-, m- or p-ethylphenyl, o-, m- or p-isopropylphenyl, o-, m- orp-t-butylphenyl, phenylphenyl, 4-methyl.1-naphthyl, 4-ethyl-1 -naphthyl,4-isopropyl-1-naphthyl or 4-t-butyl-1-naphthyl or the group ##STR16##

Particularly preferred substituent groups R are those listed abovecontaining from 6 to 20 carbon atoms, as well as the group having theformula:- ##STR17## wherein R₁₀ and R₁₁ are the same or different andeach is an alkyl group having from 1 to 6, preferably 1 to 4 carbonatoms such as methyl, ethyl, n-propyl, isopropyl, sec.butyl, t-butyl,t-pentyl, (1,1-dimethylpropyl), t-hexyl (1,1-dimethylbutyl), butpreferably methyl, isopropyl or t-butyl groups; ##STR18##

When n₁ is 2, R can be methylene, 1,2-ethylene, 1,4-n-butylene,1,8-n-octylene, 2,2,4-trimethyl-1, 4-butylene, 1,10-n-decylene,1,2-eicosylene, vinylene, propenylene, 1,2-, 1,3- and 1,4-cyclohexylene,cyclohexyl-3-ene, 1,2-, 1,3- and 1,4-phenylene, p-xylylene, 1,4-, and1,5-naphthylene, diphenylene or diphenylmethylene.

Specific examples of compounds having the formula Ia are shown on thepreceding pages to.

A further preferred sub-group of compounds of formula I are those havingthe formula:- ##STR19## and its salts wherein Y₁ is an alkyl residuehaving from 1 to 12 carbon atoms, an alkenyl residue having from 3 to 12carbon atoms or an aralkyl residue having from 7 to 9 carbon atoms andR₁₂ is hydrogen or an alkyl or alkylen containing up to 20 carbon atoms,an substituted alkyl having the formula ##STR20## wherein m is 1, 2 or3, R₄ is hydrogen or methyl.

X₁ is halogen or methoxy and

X₂ is halogen or R₁₂ is an alkenyl or alkenylen having up to 20 carbonatoms, a cycloalkyl or cycloalkyliden having 5 to 12 carbon atoms, anaryl or arylen having 6 to 12 carbon atoms and q is 1 or 2.

Two sub-groups of compounds of the formula Ib are those having as Y₁alkyl from 1 to 4 and alkyl having 5 to 12 carbon atoms.

When q is 1, R₁₂ can be for example hydrogen, methyl, ethyl, n-propyl,isopropyl, n-butyl, secbutyl, t-butyl, n-pentyl, 2-ethylpropyl,2-methylbutyl, n-hexyl, 2-methylpentyl, n-heptyl, 2-ethylpentyl,n-octyl, 2-ethylhexyl, 2,2,4-trimethylpentyl, n-decyl, n-dodecyl,n-tetradecyl, n-octadecyl, eicosyl, mesityl, allyl, oleyl, cyclopentyl,cyclohexyl, methylcyclohexyl, t-butylcyclohexyl, t-octylcyclohexyl,cyclododecyl, 1- and 2-perhydronaphthyl, adamantyl, cyclopentylmethyl,cyclohexylmethyl, β-cyclohexylethyl, benzyl, β-Phenylethyl, 1- and2-naphthylmethyl, β[1- and 2-naphthyl]ethyl, phenyl, o-, m- and p-tolyl,2,4- and 2,6-xylyl, p-chlorophenyl, 3-chloro-p-tolyl, o-ethylphenyl,p-t-butylphenyl, 2,3- and 2,5-di-chlorophenyl, α- and β-naphthyl,phenylphenyl. Preferred monovalent groups R₁₂ are hydrocarbyl groupssuch as methyl, ethyl, propyl, isopropyl, n-butyl, 2-ethylhexyl,dodecyl, octadecyl, allyl, oleyl, cyclohexyl, benzyl, phenyl, o-, m- andp-tolyl, 2,4- and 2,6-xylyl and naphthyl.

When q is 2, R₁₂ can be for example methylene, 1,2-ethylene,1,4-n-butylene, 1,6-n-hexylene, 1,8-n-octylene,2,4,4-trimethyl-1,6-hexylene, 1,10-n-decylene, 1,2-eicosylene,1,2-eicosenylene, 1,3-and 1,4-cyclohexylene, 1,3- and 1,4-phenylene,2,4-tolylene, 1,5-naphthylene, 4,4'-diphenylene, 4,4'-diphenylmethylene,3,3'-dimethyl-4,4'-diphenylene, 3,3'-dimethyl-4,4'-diphenylmethylene.

Preferred divalent groups R₁₂ are 1,2-ethylene, 1,6-hexylene,2,4,4-trimethyl-1,6-hexylene, 1,3- and 1,4-phenylene, 2,4-tolylene,1,5-naphthylene, 4,4'-diphenylmethylene.

In the above formula Ib, examples of the group Y₁ are methyl, ethyl,n-propyl, isopropyl, n-butyl, secbutyl, n-hexyl, n-octyl, n-dodecyl,allyl, α-methallyl, 10-undecenyl, benzyl, α-methylbenzyl,p-methylbenzyl, p-methyl-α-methylbenzyl, α-naphthylmethyl. Particularlypreferred are straight or branched alkyl having 1 to 4 carbon atoms andfor reasons of ease of preparation the most preferred meaning for Y₁ ismethyl.

Specific examples of the crbamoyloxy derivatives ofN-substituted-2,2,6,6-tetrasubstituted piperidin-4-ols of formula Ic aregiven in the preceding pages 19 and 20.

The following groups A to O are subgroups of compounds of the formula I.

A. Compounds of formula I wherein when n is 1, R₃ is a monovalentresidue and is an alkyl residue having from 1 to 20 carbon atoms, acycloalkyl residue having from 5 to 12 carbon atoms, an alkenyl oralkynyl residue having from 3 to 20 carbon atoms, an aralkyl residuehaving from 7 to 12 carbon atoms, or a residue having the formula:-

wherein m is 1, 2 or 3, R₄ is a hydrogen, methyl or phenyl residue, X₂is halogen, cyano, ##STR21## --COR₅, --CO.OR₅, --CO.SR₅ or --CONR₅ R₆and X₁ is hydroxyl, halogen, cyano, -OR₅, ##STR22## wherein R₅ is analkyl residue having from 1 to 20 carbon atoms, an alkenyl residuehaving from 2 to 20 carbon atoms, a cycloalkyl residue having from 5 to12 carbon atoms, an aryl residue having from 6 to 11 carbon atoms or anaralkyl residue having 7 to 14 carbon atoms or when R₅ is joined to anitrogen atom, also hydrogen and R₆ is hydrogen or an alkyl residuehaving from 1 to 4 carbon atoms, or R₅ and R₆ together with the nitrogenatom to which they are bound form a 5- or 6-membered ring which containsno other heteroatoms or contains one or more other heteroatoms or R₃ isan aryl residue or a residue having the formula:- ##STR23## wherein R₁ 'is hydrogen or R₁ ' has the same significance as R₁ of formula I; when nis 2, R₃ is a divalent residue and is an alkylene residue from 1 to 20carbon atoms, an alkenylene residue having from 2 to 20 carbon atoms, analkynylene residue having from 2 to 20 carbon atoms, a cycloalkylidenresidue having from 3 to 12 carbon atoms, an arylene residue having 6 to14 carbon atoms, an aralkylene residue having from 8 to 14 carbon atoms;

when n is 3, R₃ is a trivalent residue and is an alkanetriyl, anarenetriyl or an arenetriyl-trialkylene residue, and when n is 4, R₃ isa tetravalent residue and is an alkanetetrayl residue. B. Compounds ofthe formula I wherein when n is 1 R₃ is an acyl group ##STR24## whereinR₇ is hydrogen, an unsubstituted aliphatic or substituted aliphaticresidue having from 1 to 20 carbon atoms, an alkenyl or alkynyl residuehaving from 2 to 20 carbon atoms, a cycloaliphatic residue having from 5to 12 carbon atoms, an araliphatic residue having from 7 to 14 carbonatoms, an aromatic residue having from 6 to 20 carbon atoms or anheterocyclic residue,

or R₃ represents a monovalent group obtained by removing a hydroxylgroup from a sulphinic acid, a sulphonic acid, a phosphorus containingacid or a boric acid, when n is 2, R₃ is an divalent residue of analiphatic, aromatic or heterocyclic diacyl, the group --CO-- or--CO.CO-, a sulphinyl or sulphonyl residue or a divalent residueobtained by removing two hydroxyl groups from a disulphonic acid, aphosphorus containing acid or a boric acid;

when n is 3, R₃ is a trivalent residue of an aliphatic or aromatictriacyl residue or a triacyl residue derived from o-phosphoric,o-phosphorous or o-boric acid;

and when n is 4, R₃ is a tetravalent residue of a tetraacyl residuederived from an aliphatic or aromatic tetracarboxylic acid or fromo-silicic acid.

C. Compounds of the formula I wherein n is 1 or 2 and when n is 1

R₃ is carbamoyl residue having the formula: ##STR25## wherein R₈ ishydrogen or an alkyl residue having from 1 to 4 carbon atoms, and R₉ ishydrogen, an alkyl residue having from 1 to 20 carbon atoms, an alkenylresidue having from 3 to 20 carbon atoms, a cycloalkyl residue havingfrom 5 to 12 carbon atoms or an unsubstituted aryl or substituted arylresidue having from 6 to 12 carbon atoms;

and when n is 2 R₃ is divalent aliphatic or aromatic dicarbamoylresidue.

D. Compounds of the formula I wherein n is 1 or 2 and when n is 1

R₃ is a thiocarbamoyl residue having the formula: ##STR26## wherein R₈is hydrogen or an alkyl residue having from 1 to 4 carbon atoms, and R₉is hydrogen, an alkyl residue having from 1 to 20 carbon atoms, analkenyl residue having from 3 to 20 carbon atoms, a cycloalkyl residuehaving from 5 to 12 carbon atoms or an unsubstituted aryl or substitutedaryl residue having from 6 to 12 carbon atoms;

and when n is 2, R₃ is a divalent aliphatic or aromatic dithiocarbamoyl.

E. Compounds of the formula I wherein when n is 1

R₃ is a monovalent residue and is an alkyl residue having from 1 to 20carbon atoms, a cycloalkyl residue having from 5 to 12 carbon atoms, analkenyl or alkynyl residue having from 3 to 20 carbon atoms, an aralkylresidue having from 7 to 9 carbon atoms, or a residue having theformula:

wherein m is 1, 2 or 3, R₄ is a hydrogen, methyl or phenyl residue, X₂is halogen, cyano, ##STR27## --COR₅, --CO.OR₅, --CO.SR₅ or --CONR₅ R₆and X₁ is hydroxyl, halogen, cyano, --OR₅, --O-CO.R₅, --OCSR₅,--O.CO.NR₅ R₆, --CO.R₅, --CO.OR₅, --CO.SR₅, --CO.NR₅ R₆ or --CS.NR₅ R₆,

wherein R₅ is an alkyl residue having from 1 to 20 carbon atoms, analkenyl residue having from 2 to 20 carbon atoms, a cycloalkyl residuehaving from 5 to 12 carbon atoms, an aryl residue having from 6 to 11carbon atoms, or an aralkyl residue having 7 to 11 carbon atoms, or whenR₅ is joined to a nitrogen atom, also hydrogen and R₆ is hydrogen or analkyl residue having from 1 to 4 carbon atoms, or R₅ and R₆ togetherwith the nitrogen atom to which they are bound form a 5- or 6-memberedring which contains no other heteroatoms or contains one or more otherheteroatoms or R₃ is an aryl residue or a residue having the formula:##STR28## wherein R₁ ' is hydrogen or R₁ ' has the same significance asR₁ of claim 2;

when n is 2, R₃ is a divalent residue and is an alkylene residue havingfrom 1 to 20 carbon atoms, an alkenylene residue having from 3 to 20carbon atoms, an alkynylene residue having from 3 to 20 carbon atoms, anarylene residue having 6 to 14 carbon atoms, an aralkylene residuehaving from 8 to 14 carbon atoms;

when n is 3, R₃ is a trivalent residue of an alkanotriyl, an arenetriyl,or arenetriyltrialkylene group; and when n is 4, R₃ is a tetravalentresidue of an alkanetetrayl group.

F. Compounds of the formula I wherein when n is 1 R₃ is an acyl group##STR29## wherein R₇ is an aliphatic or substituted aliphatic residuehaving from 1 to 20 carbon atoms, an alkenyl or alkynyl residue havingfrom 2 to 20 carbon atoms, a cycloaliphatic residue having from 5 to 12carbon atoms, an araliphatic residue having from 7 to 14 carbon atoms,an aromatic residue having from 6 to 12 carbon atoms or an heterocyclicresidue, with the proviso that only one of R₁ and R₃ can represent anunsaturated acyl group or R₃ represents a monovalent group obtained byremoving a hydroxyl group from a sulphinic acid, a sulphonic acid, aphosphorous containing acid or a boric acid;

when n is 2, R₃ is a divalent residue of an aliphatic, aromatic orheterocyclic diacyl residue, a carbonyl, sulphinyl or sulphonyl residueor a divalent residue obtained by removing two hydroxyl groups from adisulphonic acid, a phosphorus containing acid or a boric acid;

when n is 3, R₃ is a trivalent residue of an aliphatic or aromatictriacyl residue or a triacyl residue derived from o-phosphoric,o-phosphorous or o-boric acid and when n is 4, R₃ is a tetravalentresidue of a tetraacyl residue derived from an aliphatic or aromatictetracarboxylic acid or from o-silicic acid.

G. Compound of the formula I wherein n is 1 or 2 and when n is 1, R₃ isa carbamoyl residue having the formula: ##STR30## wherein R₈ is hydrogenor an alkyl residue having from 1 to 4 carbon atoms, and R₉ is hydrogen,an alkyl residue having from 1 to 20 carbon atoms, an alkenyl residuehaving from 3 to 20 carbon atoms, a cycloalkyl residue having from 5 to12 carbon atoms or an aryl or substituted aryl residue having from 6 to12 carbon atoms; and when n is 2, R₃ is a divalent residue of analiphatic or aromatic dicarbamoyl residue.

H. Compounds of the formula I wherein n is 1 or 2 and when n is 1, R₃ isa thiocarbamoyl residue having the formula: ##STR31## wherein R₈ ishydrogen or an alkyl residue having from 1 to 4 carbon atoms, and R₉ ishydrogen, an alkyl residue having from 1 to 20 carbon atoms, an alkenylresidue having from 3 to 20 carbon atoms, a cycloalkyl residue havingfrom 5 to 12 carbon atoms or an aryl or substituted aryl residue havingfrom 6 to 12 carbon atoms; and when n is 2, R₃ is a divalent residue ofan aliphatic or aromatic dithiocarbamoyl residue.

I. Compounds of formula I and their bicarbonate wherein n is 1, 2 or 3R₁ is alkyl having from 1 to 18 carbon atoms, benzyl or alkenyl having 3carbon atoms or a group of the formula: ##STR32## wherein R₄ ishydrogen, methyl or phenyl and X₁ is a group of the formula ##STR33##and X₂ is a group of the formula ##STR34## wherein R₃ is alkyl having 1or 2 carbon atoms or phenyl or R₁ is a group of the formula ##STR35##and R₂ is hydrogen and R₃ when n is 1 is alkyl having 3 to 18 carbonatoms, alkenyl having 3 carbon atoms, propargyl, benzyl, --CH₂ CH₂ CN ora group of the formula wherein X₂ is ##STR36## wherein R₇ is alkylhaving 1 to 19 carbon atoms, CH₃ (CH₂)₁₁ -S-CH₂ --, cycloalkyl having 6to 10 carbon atoms, alkenyl having 2 to 17 carbon atoms, unsubstitutedaralkyl having 7 to 13 carbon atoms, C₆ H₅ -CH=CH-, aralkyl substitutedby hydroxy or butyl, unsubstituted aryl having 6 to 10 carbon atoms,aryl substituted by alkyl having 1 to 4 carbon atoms, CH₃ O-, Cl, OH, or##STR37## wherein R₉ is alkyl having 1 to 8 carbon atoms, alkenyl having3 carbon atoms, cyclohexyl, unsubstituted aryl having 6 to 10 carbonatoms, aryl substituted by methyl or Cl or

R₃ when n is 2 is the group -CO-R-CO-- wherein R is alkylen having 4 to8 carbon atoms, --CH₂ CH₂ -S-CH₂ CH₂ --, vinylen, cyclohexylen, adivalent thiophen residue, unsubstituted phenylen or phenylensubstituted by ##STR38## or a group of the formula -CONHR^(I) NHCO--

wherein R^(I) is hexylen, unsubstituted arylene having 6 to 10 carbonatoms, arylene substituted by methyl or R^(I) is the group ##STR39## ora group of the formula -COCO- or butylen or R₃ when n is 3, is

J. Compounds of the formula I wherein n is 1, 2 or 4 and when n is 1, R₃is an acyl group ##STR40## wherein R₇ is hydrogen, an substitutedaliphatic residue having from 1 to 20 carbon atoms, an alkenyl oralkynyl residue having from 2 to 20 carbon atoms, a cycloaliphaticresidue having from 5 to 12 carbon atoms, an araliphatic residue havingfrom 7 to 14 carbon atoms, or heterocyclic residue, or R₃ represents amonovalent group obtained by removing a hydroxyl group from a sulphinicacid, a sulphonic acid, a phosphorus containing acid or a boric acid, or

when n is 2, R₃ is an divalent residue of heterocyclic diacyl residue ora sulphinyl or sulphonyl residue or a divalent residue obtained byremoving two hydroxyl groups from a disulphonic acid, a phosphoruscontaining acid or a boric acid; or

when n is 4, R₃ is a tetraacyl residue derived from an aliphatictetracarboxylic acid.

K. Compounds of the formula I wherein n is 1, 2 and 4 and when n is 1,R₃ is an acyl group ##STR41## wherein R₇ is hydrogen, a cycloaliphaticresidue having from 5 to 12 carbon atoms or a heterocyclic residue or R₃represents a monovalent group obtained by removing a hydroxyl group fora sulphinic acid, a sulphonic acid, a phosphorus containing acid or aboric acid or

when n is 2, R₃ is a divalent residue of a heterocyclic diacyl or asulphinyl or sulphonyl residue or a divalent residue obtained byremoving two hydroxyl groups from a disulphonic acid, a phosphoruscontaining acid or

when n is 4, R₃ is a tetraacyl residue derived from an aliphatictetracarboxylic acid.

L. Compounds of the formula I wherein n is 1, 2 or 4 and when n is 1, R₃is an acyl group ##STR42## wherein R₇ is hydrogen, a substitutedaliphatic residue having from 1 to 20 carbon atoms, an alkenyl oralkynyl residue having from 2 to 20 carbon atoms, a cycloaliphaticresidue having from 5 to 12 carbon atoms, an araliphatic residue havingfrom 7 to 14 carbon atoms, or an heterocyclic residue, or R₃ representsa monovalent group obtained by removing a hydroxyl group from asulphinic acid, a sulphonic acid, a phosphorus containing acid or aboric acid, or

when n is 2, R₃ is a divalent residue of heterocyclic diacyl residue ora sulphinyl or sulphonyl residue or a divalent residue obtained byremoving two hydroxyl groups from a disulphonic acid, a phosphorouscontaining acid or a boric acid; or

when n is 4, R₃ is a tetraacyl residue derived from an aliphatictetracarboxylic acid.

M. Compounds of the formula I wherein n is 1, 2 and 4 and when n is 1,R₃ is an acyl group ##STR43## wherein R₇ is hydrogen, a cycloaliphaticresidue having from 5 to 12 carbon atoms or a heterocyclic residue or R₃represents a monovalent group obtained by removing a hydroxyl group froma sulphinic acid, a sulphonic acid, a phosphorus containing acid or aboric acid or

when n is 2, R₃ is a divalent residue of a heterocyclic diacyl or asulphinyl or sulphonyl residue or a divalent residue obtained byremoving two hydroxyl groups from a disulphonic acid, a phosphoruscontaining acid or

when n is 4, R₃ is a tetraacyl residue derived from an aliphatictetracarboxylic acid.

N. Compounds of the formula I wherein

when n is 1, R₃ is an acyl group ##STR44## wherein R₇ is anunsubstituted aliphatic residue having from 1 to 20 carbon atoms or anaromatic residue having from 6 to 20 carbon atoms and

when n is 2, R₃ is an divalent aliphatic or aromatic diacyl residue orthe groups -CO- or -COCO-- and

when n is 3, R₃ is a trivalent residue and is an aliphatic or aromatictriacyl residue or a triacyl residue derived from o-phosphoric,o-phosphorous or o-boric acid and

when n is 4, R₃ is a tetravalent residue of a tetraacyl residue derivedfrom an aromatic tetracarboxylic acid or from o-silicic acid.

O. Compounds of the formula I wherein

when n is 1, R₃ is an acyl group ##STR45## wherein R₇ is anunsubstituted aliphatic residue having from 1 to 20 carbon atoms or anaromatic residue having from 6 to 12 carbon atoms and

when n is 2, R₃ is an divalent aliphatic or aromatic diacyl residue orthe carbonyl group and

when n is 3, R₃ is a trivalent residue and is an aliphatic or aromatictriacyl residue or a triacyl residue derived from o-phosphoric,o-phosphorous or o-boric acid and

when n is 4, R₃ is a tetravalent residue of a tetraacyl residue derivedfrom an aromatic tetracarboxylic acid or from o-silicic acid.

The following groups P and Q are sub-groups of the compounds of formulaIa.

P. Compounds of the formula Ia wherein n is 1 and R is hydrogen or amonovalent alicyclic residue having from 5 to 12 carbon atoms.

Q. Compounds of the formula Ia wherein

when n is 1, R is a monovalent aliphatic residue having from 1 to 20carbon atoms or a monovalent aromatic residue having from 6 to 20 carbonatoms and

when n is 2, R is a divalent aliphatic residue having from 1 to 20carbon atoms or a divalent aromatic residue having from 6 to 20 carbonatoms.

The following compounds of the formula I are also a group of compoundsof the present invention. ##STR46## wherein n is 1, 2, 3 or 4; R₁ is amonovalent residue and is an alkyl residue having from 1 to 20 carbonatoms, a cycloalkyl residue having from 5 to 12 carbon atoms, an alkenylor alkynyl residue having from 3 to 20 carbon atoms, an aralkyl residuehaving from 7 to 9 carbon atoms, or a residue having the formula:-##STR47## wherein m is 1, 2 or 3, R₄ is a hydrogen, methyl or phenylresidue, X₂ is halogen, cyano, ##STR48## --COR₅, --CO.OR₅, -CO.SR₅,-CONR₅ R₆ or -CS.NR₅ R₆ and X₁ is hydroxyl, halogen, cyano, ##STR49##--OR₅, -O-CO.R₅, OCSR₅, --O.CO.NR₅ R₆, --CO.R₅, --CO.OR₅, --CO.SR₅,--CO.NR₅ R₆, --CS.NR₅ R₆, or --SR₅, wherein R₅ is an alkyl residuehaving from 1 to 20 carbon atoms, an alkenyl residue having from 2 to 20carbon atoms, a cycloalkyl residue having from 5 to 12 carbon atoms, anaryl residue having from 6 to 11 carbon atoms or when R₅ is joined to anitrogen atom, also hydrogen, and R₆ is hydrogen or an alkyl residuehaving from 1 to 4 carbon atoms, or R₅ and R₆ together with the nitrogenatom to which they are bound form a 5- or 6-membered ring which containsno other heteroatom or contains one or more other heteroatoms or R₁ isan acyl group, an unsubstituted or N-substituted carbamoyl orthiocarbamoyl group; R₂ is an alkyl residue having from 1 to 4 carbonatoms, an alkenyl or alkynyl residue having 3 to 20, carbon atoms, acycloalkyl residue having from 5 to 12 carbon atoms, an aryl residuehaving from 6 to 11 carbon atoms or an aralkyl residue having from 7 to9 carbon atoms or also hydrogen, and when n is 1, R₃ is a monovalentradical having the same significance as R₁, with the proviso that onlyone of R₁ and R₃ can represent an unsaturated acyl group or R₃represents a monovalent group obtained by removing a hydroxyl group froma sulphinic acid, a sulphonic acid, a phosphorus containing acid or aboric acid, or R₃ is an aryl residue or a residue having the formula:-##STR50## wherein R₁ ' is hydrogen or R₁ ' has the same significance asR₁.

When n is 2, R₃ is a divalent residue and is an alkylene residue havingfrom 1 to 20 carbon atoms, an alkenylene residue having from 3 to 20carbon atoms, an alkynylene residue having from 3 to 20 carbon atoms, anarylene residue having 6 to 14 carbon atoms, an aralkylene residuehaving from 8 to 14 carbon atoms or an aliphatic, aromatic orheterocyclic diacyl residue, an aliphatic or aromatic dicarbamoyl ordithiocarbamoyl, a carbonyl, sulphinyl or sulphonyl residue or adivalent residue obtained by removing two hydroxyl groups from adisulphonic acid, a phosphorus containing acid or a boric acid; when nis 3, R₃ is a trivalent residue or an aliphatic or aromatic triacylresidue or a triacyl residue derived from o-phosphoric, o-phosphorous oro-boric acid or an alkanetriyl, an arenetriyl, or arenetriyltrialkylenegroup; and when n is 4, R₃ is a tetravalent residue and is a tetravalentaliphatic residue or tetraacyl residue derived from an aliphatic oraromatic tetracarboxylic acid or from o-silicic acid or an alkanetetraylgroup; as well as partial ethers, esters and carbamoyloxy andthiocarbamoyloxy compounds related to the fully reacted compounds offormula I.

The following compounds of the formula II are also a group of compoundsof the present invention. ##STR51## and their salts, wherein R' and R"are the same or different and each is a straight or branched alkylgroup, having from 1 to 4 carbon atoms, or R' and R" together with thecarbon atom to which they are attached form a cycloalkyl residue havingfrom 5 to 12 carbon atoms; Y is an alkyl group having from 1 to 20carbon atoms, preferably 1 to 4, carbon atoms, alkenyl having from 2 to20 carbon atoms or an aralkyl residue having from 7 to 9 carbon atomsand n₁ is 1 or 2; when n is 1, R is hydrogen or a monovalent aliphaticresidue having from 1 to 20, preferably 6 to 20 carbon atoms, amonovalent alicyclic residue having from 5 to 12 carbon atoms, or amonovalent aromatic residue having from 6 to 20 carbon atoms; and when nis 2, R is a divalent aliphatic residue having from 1 to 20, preferably1 to 20, carbon atoms, and is unsubstituted or substituted orinterrupted by one or more, preferably one, sulphur atom, a divalentalicyclic residue having from 5 to 12 carbon atoms or a divalentaromatic residue having from 6 to 20 carbon atoms.

Subgroups of the compounds of formula II are

a. Compounds wherein Y is methyl or

b. Compounds wherein n is 1 and R is a monovalent aliphatic, alicyclicor aromatic residue having from 6 to 20 carbon atoms and this group hasthe formula: ##STR52## wherein R₁₀ and R₁₁ are the same or different andeach is an alkyl group having from 1 to 6 carbon atoms, A is ##STR53##or --CH₂ CH₂ -- and p is 0 or 1, or c. Compounds wherein R₁₀ and R₁₁ aremethyl, isopropyl or t-butyl groups or

d. Compounds wherein n is 2 and R is a methylene, 1,2-ethylene,1,4-butylene, 1,8-n-octylene, 2,2,4-trimethyl-1, 4-butylene,1,10-n-decylene, 1,2-eicosylene, vinylene, propenylene, 1,2-, 1,3- or1,4-cyclohexylene, cyclohexyl-3-ene, 1,2-, 1,3- or 1,4-phenylene,p-xylylene, 1,4- or 1,5-naphthylene, diphenylene or diphenylmethyleneresidue or the group --CH₂ CH₂ S CH₂ CH₂ -- or R is absent.

e. Compounds in the form of its salt of an inorganic or organic acid.

f. Compounds wherein the salt is a phosphate, carbonate, sulphate,chloride, acetate, stearate, maleate, nitrate, tartrate, oxalate,benzoate or substituted carbamate.

g. Compounds wherein R' and R" are methyl.

The following compounds of the formula IV are also compounds of thepresent invention: ##STR54## and its salts wherein R^(III) and R^(IV)are the same or different and each is a straight- or branched alkylresidue having from 1 to 12 carbon atoms or R^(III) and R^(IV) togetherwith the carbon atom to which they are each attached form a cycloalkylgroup having from 5 to 12 carbon atoms, Y is a straight- or branchedalkyl residue having from 1 to 12 carbon atoms, an alkenyl residuehaving from 3 to 12 carbon atoms or an aralkyl residue having from 7 to12 carbon atoms and R₁₂ is hydrogen or a saturated or unsaturatedhydrocarbyl residue containing up to 20 carbon atoms optionallysubstituted, Y halogen or alkoxy having from 1 to 4 carbon atoms and qis 1 or 2.

Sub-groups of the compounds of the formula IV are:

a. Compounds wherein q is 1 and R₁₂ is an aliphatic residue having from1 to 20 carbon atoms, an alicyclic residue having from 5 to 12 carbonatoms or an aromatic residue having from 6 to 12 carbon atoms.

b. Compounds wherein R₁₂ is a methyl, ethyl, propyl, isopropyl, n-butyl,2-ethylhexyl, dodecyl, octadecyl, allyl, oleyl, cyclohexyl, benzyl,phenyl, o-, m- or p-tolyl, 2,4- or 2,6-xylyl or a naphthyl residue.

c. Compounds wherein q is 2 and R₁₂ is an aliphatic residue having from1 to 20 carbon atoms, an alicyclic residue having from 5 to 15 carbonatoms or an aromatic residue having from 6 to 15 carbon atoms.

d. Compounds wherein R₁₂ is a 1,2-ethylene, 1,6-hexylene,2,4,4-trimethyl-1,6-hexylene, 1,3- or 1,4-phenylene, 2,4-tolylene,1,5-naphthylene or 4,4'-diphenylmethylene residue.

e. Compounds wherein Y₁ is methyl.

f. Compounds in the form of its salt of an inorganic or organic acid.

g. Compounds wherein the salt is a phosphate, carbonate, sulphate,chloride, acetate, carbonate, sulphate, chloride, acetate, stearate,maleate, citrate, tertrate, oxalate, benzoate or substituted carbamate.

h. Compounds wherein R^(III) and R^(IV) are methyl.

According to the present invention, there is also provided a firstprocess in which a compound of formula I is produced, comprisingreacting, in the presence of an acidbinding agent, a piperidinol havingthe formula:- ##STR55## wherein R₁ and R₂ have their previoussignificance, with an acid halide having the formula:-

    R.sub.3 - (CO hal).sub.n                                   VI

wherein R₃ and n have their previous significance and hal represents ahalogen atom, preferably a chlorine atom.

Suitable acid binding agents are organic bases such as triethylamine;alternatively, an excess amount of the amine V can serve as the acidbinding agent.

The reaction is conveniently carried out by heating the reactantstogether in a solvent such as cyclohexane, benzene or toluene which isinert under the reaction conditions. When the reaction is complete, thedesired product is then separated by conventional techniques.

The present invention also provides a second process in which a compoundof formula I is produced, comprising reacting, in the presence of atransesterification catalyst, a piperidinol compound of formula V, ashereinbefore defined, with an ester having the formula:-

    R.sub.3 - (CO.sub.2 R.sub.13).sub.n                        VII

wherein R₃ and n have their previous significance and R₁₃ is an alkylresidue having from 1 to 4 carbon atoms, preferably 1 or 2 carbon atoms.

Examples of suitable transesterification catalysts are alkali metalamides such as lithium amide.

A third process according to this invention in which a compound offormula I is produced comprises reacting, in the presence of anesterification catalyst, a piperidinol compound of formula V, ashereinbefore defined, with an acid having the formula:-

    R.sub.3 (CO.sub.2 H).sub.n                                 VIII

wherein R₃ and n have their previous significance.

Suitable examples of esterification catalysts are neutral catalysts suchas tetraalkyl titanates such as tetrabutyl titanate.

The second and third processes of the invention are convenientlyeffected by mixing the reactants together in the presence or absence ofan inert solvent (for instance, benzene, toluene, xylene etc.) andagitating the reaction mixture until reaction is complete, asdetermined, for instance, by collecting the alcohol or water produced inthe reaction, and stopping the reaction when the theoretical amount ofalcohol or water, respectively, has been removed.

A fourth process in which a compound of formula I is produced comprisesreacting a compound having the formula:- ##STR56## wherein R₂, R₃ and nhave their previous significance, with a compound X capable of reactionwith the compound IX and of introducing into it the group R₁ ashereinbefore defined.

For instance, compound X may be an alkylating, alkenylating oraralkylating agent such as the halides of these groups. Compound X mayalso be the aldehyde or ketone corresponding to the substituent R₁, sothat, when reacted with a compound of formula IX under Leuckart, Wallachor Eschweilar-Charles reaction conditions, compounds of formula I inwhich R₁ is methyl may be produced by reacting a compound of formula IXwith formic acid and formaldehyde.

The starting-materials of formulae V, VI, VII, VIII, IX and X used inthe processes of this invention can all be produced by methodswell-known per se. The compounds of formula V are described in ourcopending British Pat. Application No. (Case 37/72) and those of formulaIX are described generally in German Patent Specification No. 1,929,928.

Compounds of the general formula I in which b = 2, 3 or 4 and R₃represents a di-, tri- or tetra-valent radical derived from an alkyl,alkenyl, aryl or aralkyl radical may be prepared by reacting a compoundof the formula: ##STR57## R₁ and R₂ has its previous significance, witha compound of the formula R₃ (X₄)_(n) wherein X₄ is a halogen atom and nis 2, 3 or 4. This reaction is preferably carried out by making thesodium salt of the piperidine compound and reacting this with thecompound R₃ (X₄)_(n).

The substituents R₁ may be introduced before or after R₃ or in the casewhere R₁ and R₃ are identical may be introduced together by reacting acompound of the formula: ##STR58## with an alkylating, alkenylating,alkynylating, aralkylating, acylating agent or carbamoyloxyating agent,with an alkylating, alkenylating, alkynylating, aralkylating oracylating agent.

Compounds of formula I in which R₁ represents a residue of the formula:##STR59## in which R₄ is as defined above, m is 1 and X₁ represents -CN,-OR₅, ##STR60## R₅ and R₆ being as defined above, may be produced byreacting a compound of the formula: ##STR61## wherein R₃ and R₂ are asdefined above, with a compound having the formula ##STR62## Compounds offormula I wherein m is 1 and X₁ is -OH may be prepared by reacting acompound of formula XII with ethylene oxide, propylene oxide or styreneoxide.

Compounds of formula I wherein R₁ is ##STR63## or halogen may beprepared from the corresponding compounds wherein X₁ is -OH by standardmethods, such as alkylation, esterification, carbamoyloxylation orhalogenation.

Compounds of formula I in which R₁ represents a residue of formula:-##STR64## wherein m, R₄ and X₁ are as hereinbefore defined may beprepared by reacting a compound of formula XII with the appropriatehalogen compound having the formula:- ##STR65## wherein X₃ is a halogenatom.

Compounds of formula I in which R₁ is the group of formula:- ##STR66##wherein X₂ and R₄ are as defined above may be prepared by reacting acompound of the formula XII wherein R₂ is as defined above with acompound of the formula ##STR67## wherein X₄ is a halogen atom.

Compounds of the general formula I in which R₁ represents an acyl groupmay be prepared by reacting a compound of the formula: ##STR68## whereinR₂ and R₃ are as defined above with an acyl halide of the formula##STR69## wherein X₅ is a halogen, and R₁₄ is the remainder of the acylgroup.

Compounds of the general formula I in which R₁ represents a carbamoyl orthiocarbamoyl group may be prepared by reacting a compound of theformula: ##STR70## R₂ and R₃ being as defined above with an isocyanateor thioisocyanate of the formula R₁₅ NCX¹ in which X¹ is ##STR71## andR₁₅ is the remainder of the isocyanate or thioisocyanate group.

Where R₂ in the general formula I is other than hydrogen it is preferredto introduce the appropriate group before or after the group R₁ isintroduced, but before R₃ is introduced. The group R₂ may be introducedby reacting a ketone of the formula: ##STR72## wherein R₁ ¹ is hydrogenor R₁, with a Grignard reagent R₂ MgX followed by hydrolysis to producea compound of the formula: ##STR73##

All the reactions described above which result in the elimination ofhydrogen halide between two reactants may be carried out in the presenceof an acid acceptor.

Compounds of formula II as defined hereinbefore are produced byreacting, in the presence of an acid-binding agent, a piperidinolcompound having the formula: ##STR74## wherein Y, R' and R" are asdefined hereinbefore with an acid halide having the formula:

    R-(CO hal.).sub.n

wherein R and n are as defined hereinbefore and hal. represents ahalogen atom. The acid binding agent can be an organic or an excessamount of the amine reactant XIV and the reactants are for exampleheated together in a solvent inert under the reaction conditions.

The process can be performed in the presence of a transesterificationcatalyst, such as an alkali metal, a piperidinol compound having theformula XIV, with an ester having the formula:

    R-(CO.sub.2 R.sub.16).sub.n

wherein R and n are as defined above and R₁₆ is an alkyl group havingfrom 1 to 4 carbon atoms, or with an acid having the formula:

    R-(CO.sub.2 H).sub.n

wherein R and n are as defined above.

The catalyst of producing compounds of the formula II can be a neutralcatalyst such as tetraalkyl titanate.

In the process for producing compounds of the formula II the reactantscan also be fused, the mass is agitated until reaction is complete andthe reaction is stopped when the reaction is complete. The completion ofthe reaction is determined for example by collecting, respectively, thealcohol or water produced in the reaction, and stopping the reactionwhen the theoretical amount of water or alcohol has been removed.

Compounds of formula II are also produced by reacting an ester havingthe formula: ##STR75## wherein R, R', R" and n are as defined above witha compound capable of reacting with the ester XV such as an alkylatingor aralkylating agent or an aldehyde or ketone corresponding to thesubstituent Y and of introducing into it the group Y as defined above.

Compounds having the formula IV as defined hereinbefore are produced byreacting a compound having the formula: ##STR76## wherein Y, R¹¹¹ andR^(IV) are as defined hereinbefore with an isocyanate having theformula:

    R.sub.12 (NCO).sub.q

wherein R₁₂ and q are as defined hereinbefore. The reaction can beeffected in a solvent inert under the reaction conditions and in thepresence of a strong base.

The present invention still further provides a composition comprising anorganic material and a stabilising amount of a compound having theformula I, II or IV as hereinbefore defined.

Compounds of formula I, II or IV, have been found to impart topolyolefines an exceptionally high degree of stability towardsdeterioration normally induced by the effects of ultra-violet radiationor exposure to heat. Moreover, this improved stability is achievedwithout affecting the colour properties of the treated polyolefine. Thestabilisers of the invention provide effective light and/or heatstabilisation, especially for low- and high-density polyethylene andpolypropylene and polystyrene as well as polymers of butene-1,pentene-1, 3-methyl-butene-1, hexene-1, 4-methylpentene-1,4-methylhexene-1 and 4,4-dimethyl-pentene-1, and also co- andter-polymers of olefines, particularly of ethylene or propylene.

Other organic materials susceptible to degradiation by the effects oflight and the properties of which are improved by the incorporationtherein of a compound of formula I, II or IV, include natural andsynthetic polymeric materials, for instance natural and syntheticrubbers, the latter including, for example, homo-, co- and ter-polymersof acrylonitrile, butadiene and styrene.

Specific synthetic polymers include polyvinyl chloride, polyvinylidenechloride and vinyl chloride co-polymers, polyvinyl acetate as well ascondensation polymers derived from ether, ester (derived from carboxylicsulphonic or carbonic acids), amide or urethane groupings. Thesepolymers can, for instance, form the basis of surface coating media suchas paints and lacquers having an oil or resin, for instance an alkyd orpolyamide resin base.

The amount of the compound of formula I, II or IV, which is incorporatedinto the organic material in order to achieve maximal protection againstdegradation by light varies according to the properties of the organicmaterial treated and according to the severity of the light radiationand to the length of exposure. However, for most purposes it issufficient to use an amount of the compound of formula I, II or IV,within the range of from 0.01% to 5% by weight, more preferably withinthe range of from 0.1% to 2% by weight based on the weight of untreatedorganic material.

The compounds may be incorporated into the polymeric material by any ofthe known techniques for compounding additive with a polymer. Forexample, the compound and the polymer may be compounded in an internalmixer. Alternatively, the compound may be added as a solution or slurryin a suitable solvent or dispersant, for instance an inert organicsolvent such as methanol, ethanol or acetone to powdered polymer and thewhole mixed intimately in a mixer, and the solvent subsequently removed.As a further alternative the compound may be added to the polymer duringthe preparation of the latter, for instance at the latex stage ofpolymer production, to provide pre-stabilized polymer material.

Optionally, the composition of the invention may contain one or morefurther additives, especially those used in polymer formulations, suchas antioxidants of the phenol or amine type, U.V. absorbers and lightprotectants, phosphite stabilisers, peroxide decomposers, polyamidestabilisers, basic co-stabilisers, polyvinyl chloride stabilisers,nucleation agents, plasticizers, lubricants, emulsifiers, anti-staticagents, flame-protectants, pigments, carbon black, asbestos, glassfibres, kaolin and talc.

The present invention therefore includes binary, tertiary andmulti-component compositions containing the stabiliser of formula I, IIor IV, together with one or more functional additives for polymers.

Examples of suitable antioxidants are those of the hindered phenol typesuch as those selected from the following groups: 1. Phenolic compoundshaving the general formula

    Q-(CH.sub.2).sub.w -A.sub.1

wherein Q is ##STR77## A₁ is --CR(COOR")₂ ##STR78## R is hydrogen orlower alkyl R' is lower alkyl

R" is alkyl group having from 6 - 24 carbon atoms

w is an integer from 0 to 4.

Illustrative examples of the compounds shown above are:

di-n-octadecyl-α-(3,5-di-t-butyl-4-hydroxy-benzyl) malonate

di-n-octadecyl-α-(3-t-butyl-4-hydroxy-5-methylbenzyl)malonate which isdisclosed in the Netherlands Pat. No. 6,711,199, Feb. 19, 1968

di-n-octadecyl-α,α'bis-(3-t-butyl-4-hydroxy-5-methylbenzyl)malonatewhich is disclosed in the Netherlands Pat. No. 6,803,498, Sept. 18,1968.

2. Phenolic compounds having the general formula

    Q-R'"

Illustrative examples of the compounds shown above are:

2,6-di-t-butyl-p-cresol

2-methyl-4,6-di-t-butylphenol and the like

2,6-di-Octadecyl-p-cresol

3. Phenolic compounds having the formula

    Q-C.sub.w H.sub.2w -Q

Illustrative examples of the compounds shown are:

2,2'-methylene-bis(6-t-butyl-4-methylphenol)

2,2'-methylene-bis(6-t-butyl-4-ethylphenol)

4,4'-butylidene-bis(2,6-di-t-butylphenol)

4,4' -(2-butylidene)-bis(2-t-butyl-5-methylphenol)

2,2'-methylene-bis[6-(2-t-methylcyclohexyl)-4methylphenol

2,2'-methylene-bis(3-t-butyl-5-ethylphenol)

4,4'-methylene-bis(3,5-di-t-butylphenol)

4,4'-methylene-bis(3-t-butyl-5-methylphenol)

2,2'-methylene-bis(3-t-butyl-5-methylphenol) and the like.

4. Phenolic compounds having the formula:

    R'"-O-Q

Illustrative examples of such compounds are:

2,5-di-t-butylhydroquinone

2,6-di-t-butylhydroquinone

2,5-di-t-butyl-4-hydroxyanisole

5. Phenolic compounds having the formula:

    Q-S-Q

Illustrative examples of such compounds are:

4,4'-thiobis-(2-t-butyl-5-methylphenol)

4,4'-thiobis-(2-t-butyl-6-methylphenol)

2,2'-thiobis-(6-t-butyl-4-methylphenol)

4,4'-thiobis-(2-methyl-5-t-butylphenol)

6. Phenolic compounds having the formula ##STR79##

Illustrative examples of such compounds are:

octadecyl-(3,5-dimethyl-4-hydroxybenzylthio)-acetatedodecyl-(3,5-di-t-butyl-4-hydroxybenzylthio)-propionate

7. Phenolic compounds having the formula ##STR80##

wherein T is hydrogen

R or Q as defined above.

Illustrative examples of such compounds are:

1,1,3-tris(3,5-dimethyl-4-hydroxyphenyl)-propane

1,1,3-tris(5-t-butyl-4-hydroxy-2-methylphenyl)-butane

1,1,5,5-tetrakis-(3'-t-butyl-4'-hydroxy-6'-methylphenyl)-n-pentane

8. Phenolic compounds having the formula: ##STR81## wherein B¹, B² andB³ are hydrogen, methyl or Q, provided that when B¹ and B³ are Q then B²is hydrogen or methyl and when B² is Q then B¹ and B³ are hydrogen ormethyl.

Illustrative examples of such compounds are:

1,4-di(3,5-di-t-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene

1,3,5-tri(3,5-di-t-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene

8. Phenolic compounds having the formula ##STR82## wherein Z is NHQ,--S-D- or --O--Q

D is alkyl group having from 6 - 12 carbon atoms

or -(C_(w) H_(2w))-S-R"

Illustrative examples of such compounds are:

2,4-bis-(n-octylthio)-6-(3,5-di-t-butyl-4-hydroxyaniline)-1,3,5-triazine

6-(4-hydroxy-3-methyl-5-t-butylanilino)-2,4-bis-(n-octyl-thio)-1,3,5-triazine

6-(4-hydroxy-3,5-dimethylanilino)-2,4-bis-(n-octylthio)-1,3,5-triazine

6-(4-hydroxy-3,5-di-t-butylanilino)-2,4-bis-(n-octyl-thio)-1,3,5-triazine

6-(4-hydroxy-3,5-di-t-butylanilino)-4-(4-hydroxy-3,5-di-t-butylphenoxy)-2-(n-octylthio)1,3,5-triazine

2,4-bis(4-hydroxy-3,5-di-t-butylanilino)-6-(n-octylthio)-1,3,5-triazineThe above phenolic triazine stabilizers are more fully described in U.S.Pat. No. 3,255,191.

10. Phenolic compounds having the formula: ##STR83## wherein Z' is -O-Q,-S-D or -S-(C_(w) H_(2w))-SD.

Illustrative examples of such compounds are:

2,3-bis-(3,5-di-t-butyl-4-hydroxyphenoxy)-6-(n-octylthio)-1,3,5-triazine

2,4,6-tris-(4-hydroxy-3,5-di-t-butylphenoxy)-1,3,5-triazine

6-(4-hydroxy-3,5-di-t-butylphenoxy)-2,4-bis-(n-octyl-thioethylthio)-1,3,5-triazine

6-(4-hydroxy-3-methylphenoxy)-2,4-bis-(n-octylthio)-1,3,5-triazine

6-(4-hydroxy-3-t-butylphenoxy)-2,4-bis-(n-octylthio-ethylthio)-1,3,5-triazine

6-(4-hydroxy-3-methyl-5-t-butylphenoxy)-2,4-bis-(n-octylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3-methyl-5-t-butylphenoxy)-6-(n-octylthio)-1,3,5-triazine

2,4,6-tris-(4-hydroxy-3-methyl-5-t-butylphenoxy)-1,3,5-triazine

6-(4-hydroxy-3,5-di-t-butylphenoxy)-2,4-bis-(n-octylthiopropylthio)-1,3,5-triazine

6-(4-hydroxy-3,5-di-t-butylphenoxy)-2,4-bis-(n-dodecyl-thioethylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-butylthio-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-octadecylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-dodecyl-thio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-octyl-thiopropylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-octyl-thioethylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-dodecylthioethylthio)-1,3,5-triazine.

The above phenolic triazine stabilizers are more fully described in U.S.Pat. No. 3,255,191.

11. Phenolic compounds having the formula

    [Q-C.sub.z H.sub.2z -COO-C.sub.z H.sub.2z ].sub.p -R'"-(R).sub.4-p

wherein p is an integer from 2 to 4 and R'" is a tetravalent radicalselected from aliphatic hydrocarbons having from 1 to 30 carbon atoms,aliphatic mono- and dithioethers having from 1 to 30 carbon atoms,aliphatic mono- and diethers having from 1 to 30 carbon atoms and z isan integer from 0 to 6.

Illustrative examples of such compounds are

Sub-class I

n-Octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate

n-Octadecyl-2-(3,5-di-t-butyl-4-hydroxyphenyl)-acetate

n-Octadecyl-3,5-di-t-butyl-4-hydroxybenzoate

n-Hexyl-3,5-di-t-butyl-4-hydroxyphenylbenzoate

n-Dodecyl-3,5-di-t-butyl-4-hydroxyphenylbenzoate

Neo-dodecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

Dodecyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

Ethyl-α-(4-hydroxy-3,5-di-t-butylphenyl)-isobutyrate

Octadecyl-α-(4-hydroxy-3,5-di-t-butylphenyl)-isobutyrate

Octadecyl-α-(4-hydroxy-3,5-di-t-butylphenyl)-propionate

Sub-class II

2-(octylthio)ethyl 3,5-di-t-butyl-4-hydroxybenzoate

2-(n-octylthio)ethyl 3,5-di-t-butyl-4-hydroxyphenyl-acetate

2-(n-octadecylthio)ethyl 3,5-di-t-butyl-4-hydroxyphenylacetate

2-(n-octadecylthio)ethyl 3,5-di-t-butyl-4-hydroxybenzoate

2-(2-hydroxyethylthio)ethyl 3,5-di-t-butyl-4-hydroxybenzoate

2,2'-Thiodiethanol bis(3,5-di-t-butyl-4-hydroxyphenyl) acetate

Diethyl glycol bis-[3,5-di-t-butyl-4-hydroxyphenyl)propionate]

2-(n-octadecylthio)ethyl 3-(3,5-di-t-butyl-4-hydroxy-phenyl)propionate

2,2'-Thiodiethanol-bis-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

Stearamido N,N-bis-[ethylene3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

n-Butylimino N,N-bis-[ethylene3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

2-(2-stearoyloxyethylthio)ethyl 3,5-di-t-butyl-4-hydroxybenzoate

2-(2-hydroxyethylthio)ethyl7-(3-methyl-5-t-butyl-4-hydroxyphenyl)heptanoate

2-(2-stearoyloxyethylthio)ethyl7-(3-methyl-5-t-butyl-4-hydroxyphenyl)heptanoate

Sub-class III

1,2-propylene glycol bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

Ethylene glycol bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

Neopentylglycol bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

Ethylene glycol bis-(3,5-di-t-butyl-4-hydroxyphenyl-acetate)

Glycerine-1-n-octadecanoate-2,3-bis-(3,5-di-t-butyl-4-hydroxyphenylacetate

Pentaethylthritol-tetrakis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

1,1,1-trimethylolethane-tris-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

Sorbitol hexa-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

1,2,3-butanetriol tris-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]

2-hydroxyethyl 7-(3-methyl-5-t-butyl-4-hydroxyphenyl)heptanoate

2-stearoxyloxyethyl 7-(3-methyl-5-t-butyl-4-hydroxyphenyl)heptanoate

1,6-n-hexanediol-bis[(3',5'-di-t-butyl-4-hydroxyphenyl)propionate]

The above phenolic ester stabilizers of sub-classes I, II and III aremore fully described in U.S. Pat. No. 3,330,859, Ser. No. 354,464, filedMar. 24, 1964 and Ser. No. 359,460, filed Apr. 13, 1964, respectively.

12. Phenolic compounds having the formula ##STR84## where x is aninteger of 1 or 2.

Illustrative examples of such compounds are

Di-n-octadecyl 3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

Di-n-octadecyl 3-t-butyl-4-hydroxy-5-methylbenzyl-phosphonate

Di-n-octadecyl 1-(3,5-di-t-butyl-4-hydroxyphenyl)-ethanephosphonate

Di-n-tetradecyl 3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

Di-n-hexyldecyl 3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

Di-n-docosyl-3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

Di-n-octadecyl 3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

The above di-(higher)alkyl phenolic phosphonates are more fullydescribed in U.S. Pat. No. 3,281,505.

13. Phenolic compounds having the formula ##STR85## wherein W and Q aredefined above.

Illustrative examples of such compounds are:

tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate

tris-(3-t-butyl-4-hydroxy-5-methylbenzyl)isocyanurate.

The above hydroxyphenylalkenyl isocyanurates are more fully described inU.S. Pat. No. 3,531,483.

The above phenolic hydrocarbon stabilizers are known and many arecommercially available.

While any of the above mentioned antioxidants can be useful incombination with the ulraviolet light stabilizers of this invention, thepreferred antioxidants consist of the hindered phenols in groups 1, 8,9, 10, 11, 12 and 13 as mentioned above. The most preferred hinderedphenols are those of groups 1, 9, 11, 12 and 13.

Further examples of antioxidants are those of the aminoaryl series forinstance aniline and naphthylamine derivatives as well as theirheterocyclic derivatives such as:

phenyl-1-naphthylamine

phenyl-2-naphthylamine

N,N'-diphenyl-p-phenyldiamine

N,n'-di-sec.butyl-p-phenylenediamine

6-Ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline

6-Dodecyl-2,2,4-trimethyl-1,2-dihydroquinoline

Mono- and di-octyliminodibenzyl and

polymerised 2,2,4-trimethyl-1,2-dihydroquinoline.

Ultraviolet absorbers and light protectants include

a. 2-(2'-hydroxyphenyl)benzotriazoles, for instance 5'-methyl;3',5'-di-t-butyl; 5'-t-butyl; 5-chloro-3',5'-di-t-butyl;5-chloro-3'-t-butyl-5'-methyl; 3'-sec.butyl-5'-tert.butyl;3'-[α-methylbenzyl]-5'-methyl-; 3'-[α-methylbenzyl]-5'-methyl-5-chloro-;4'-octoxy-; 3',5'-di-t-amyl; 3'-methyl-5'-carbamethoxyethyl;5-chloro-3',5'-di-t-amyl derivatives.

b. 2,4-bis-(2'-hydroxyphenyl)-6-alkyl-S-triazines, for instance the6-ethyl or 6-undecyl derivatives.

c. 2-hydroxybenzophenones, for instance the 4-hydroxy, 4-methoxy,4-octoxy-, 4-decyloxy-, 4-dodecyloxy-, 4,2',4'-trihydroxy or2'-hydroxy-4,4'-dimethoxy derivatives.

d. 1,3-Bis(2'-hydroxybenzoyl)-benzenes for instance,

1,3-bis-(2'-hydroxy-4'-hexyloxybenzoyl)benzene

1,3-bis(2'-hydroxy-4'-octoxybenzoyl)benzene

1,3-bis-(2'-hydroxy-4'-dodecyloxybenzoyl)benzene

e. Aryl esters from optionally substituted benzoic acids such asphenylsalicylate, octylphenylsalicylate, dibenzoyl resorcinol,bis-(4-tert.butylbenzoyl) resorcinol, benzoylresorcinol and3,5-di-tert.butyl-4-hydroxy-benzoic acid-2,4-di-tert.butyl phenyl esterand -octadecyl ester and -2-methyl-4,6-di-tert.butyl phenyl ester.

f. Acrylates, for instance

α-Cyano-β,β-diphenylacrylic acid ethyl- or iso-octyl ester,α-carbomethoxy-cinnamic acid, methyl- or butyl ester andN-(β-carbomethoxyvinyl)-2-methyl indoline.

g. Nickel compounds such as nickel complexes of2,2'-thiobis-(4-tert.octylphenol), for instance the 1:1 and 1:2complexes, optionally having other ligands such as n-butylamine,triethanolamine or N-cyclohexyl-diethanolamine; nickel complexes ofbis-(4tert.octylphenyl) sulphone such as the 2:1 complex, optionallyhaving other ligands such as 2-ethylcaproic acid; nickel dibutyldithiocarbamates; nickel salts of4-hydroxy-3,5-di-tert.butylbenzyl-phosphonic acid mono-alkyl esters suchas the methyl-, ethyl- or butyl esters: the nickel complex of2-hydroxy-4-methyl-phenyl-undecylketonoxime; andnickel-3,5-di-tert.butyl-4-hydroxy benzoate, and

h. Oxalic acid diamides, for instance

4,4'-dioctyloxyoxanilide

2,2'-dioctyloxy-5,5'-di-tert.butyl-oxanilide

2,2'-di-dodecyloxy-5,5'-di.tert.butyl oxanilide

2-ethoxy-5-tertiarybutyl-2'-ethyl-oxanilide

2-ethoxy-2'-ethyl-oxanilide

mixtures of o- and p-methoxy and ethoxy-di-substituted oxanilides andthe compound of formula: ##STR86##

Phosphite stabilisers include triphenyl phosphite, diphenylalkylphosphites, phenyl dialkyl phosphites, trinonylphenyl phosphite,trilauryl phosphite, trioctadecyl phospite,3,9-di-isodecyloxy-2,4,8,10-tetraoxa-3,9-diphosphaspiro-(5,5)-undecaneand tri-(4-hydroxy-3,5-di-tert.butylphenyl)phosphite.

Peroxide-decomposing compounds for polyolefins include esters ofβ-thiodipropionic acids, for instance the lauryl-, stearyl-, myristyl-or tridecyl esters, salts of mercaptobenzimidazoles such as the zincsalt and diphenylthiourea.

Suitable polyamide stabilisers include copper salts in combination withiodides and/or further phosphorus compounds and salts of bivalentmanganese.

Basic co-stabilisers are, for example, polyvinylpyrrolidone, melamine,benzoguanamine, triallyl cyanurate, dicyandiamide, urea derivatives,hydrazine derivatives, amines, polyamides, polyurethanes, alkali andalkaline earth salts of higher saturated or unsaturated fatty acids suchas calcium stearate.

Polyvinyl chloride stabilisers include organotin compounds, organo leadcompounds and Ba/Cd salts of fatty acids.

Examples of nucleation agents are 4-tert.butyl benzoic acid, adipic acidand diphenylacetic acid.

As with the compound of formula I, II or IV any further additive isadvantageously employed in a proportion within the range of from 0.01%to 5% by weight, based on the weight of untreated polymeric material.

In binary combinations with one or more antioxidants listed above or intertiary combinations with such antioxidants and U.V. absorbers listedabove, the compounds for formula I, II or IV provide very effectivestabiliser packages in polyolefine formulations.

Some Examples will now be given. Parts and percentages are by weightunless otherwise stated.

EXAMPLE 1

A mixture of 10.26 parts of 1,2,2,6,6-pentamethyl-piperidin-4-ol, 6.06parts of sebacic acid and 1.0 parts of tetra-n-butyl titanate in 100parts of xylene was heated under reflux conditions for 60 hours. Removalof the xylene by distillation under reduced pressure gave an oily solidwhich was heated under reflux conditions with 0.5 parts of sodiumcarbonate and 0.5 parts of carbon in 25 parts of water for 1 hour.

Removal of the water by distillation under reduced pressure gave a blackresidue which was repeatedly extracted with ether. The combined etherextracts were dried and the ether removed by distillation under reducedpressure to give a yellow oil which was distilled under reduced pressureto give 5.0 parts of bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacateas a colorless oil having a boiling point of 220°-2° C. at 0.2 mm of Hgand the following elemental analysis by weight:

    ______________________________________                                               Found    Required  (for C.sub.30 H.sub.56 N.sub.2 O.sub.4)             ______________________________________                                        Carbon   70.60 %    70.82 %                                                   Hydrogen 11.00 %    11.10 %                                                   Nitrogen  4.81 %     5.51 %                                                   ______________________________________                                    

Table I gives a list of esters prepared using the procedure of Example1.

    TABLE 1      m.p. or ANALYSIS       Example b.p. Molecular REQUIRED (%)  FOUND (%)        No. R.sub.1 R.sub.2 R.sub.3 ° C at m.m. Formula C H N  C H     N      2 CH.sub.3 H     ##STR87##      88° C C.sub.21 H.sub.33 NO.sub.2 76.09 10.03 4.23 76.36 9.90     3.99      3 CH.sub.2CH . CH.sub.2 H     ##STR88##      130° C. at0.05 m.m. Hg. C.sub.19 H.sub.33 NO.sub.2 74.22 10.82     4.56 74.86 10.65 4.26      4 CH.sub.3 H     ##STR89##      200° C at 0.1 m.m. Hg. C.sub.28 H.sub.53 NO.sub.2 77.18 12.26     3.21 78.10 12.30 3.06      5 CH.sub.3 H     ##STR90##      81-3° at0.05 m.m. Hg. C.sub.14 H.sub.27 NO.sub.2 69.67 11.27     5.80 70.16 11.37 5.90      6 CH.sub.3 H     ##STR91##      228-30° C at0.1 m.m. Hg. C.sub.28 H.sub.50 N.sub.2 O.sub.4 70.25 1     0.53 5.85 70.26 10.44 5.38      7 CH.sub.3 H     ##STR92##      91-2° C C.sub.24 H.sub.42 N.sub.2 O.sub.4 68.21 10.02 6.63 68.05 9     .97 6.47      8 CH.sub.3 H     ##STR93##      210-20° C at 0.4 m.m. C.sub.26 H.sub.48 N.sub.2 O.sub.4 S 64.40     9.98 5.78 S=6.60 64.26 9.89 5.51 S=6.59      9 CH.sub.3 H     ##STR94##      64-5°  C C.sub.26 H.sub.48 N.sub.2 O.sub.4 S 68.99 10.69 6.19     69.53 10.02 6.02      10 CH.sub.3 H     ##STR95##      57° C. C.sub.19 H.sub.27 NO.sub.2 75.71 9.03 4.65 75.50 8.97     4.71      11 CH.sub.3 H     ##STR96##      120° C. at0.2 m.m. Hg. C.sub.18 H.sub.27 NO.sub.2 74.70 9.40     4.84 74.99 9.70 4.85      12 CH.sub.3 H     ##STR97##      148° C. at0.4 m.m. Hg. C.sub.18 H.sub.27 NO.sub.2 74.70 9.40     4.84 74.98 9.42 4.70      13 CH.sub.3 H     ##STR98##      51°  C. C.sub.18 H.sub.27 NO.sub.3 70.79 8.91 4.59 70.49 8.71     4.50      14 CH.sub.3 H     ##STR99##      147° C. at0.1 m.m. Hg. C.sub.17 H.sub.24 NO.sub.2 Cl 66.00 7.81     4.52 Cl=11.44 65.98 7.65 4.53 Cl=11.5      15 CH.sub.3 H     ##STR100##      152-4° C. at0.2 m.m. Hg. C.sub.17 H.sub.24 NO.sub.2 Cl 66.00     7.81 4.52 Cl=11.44 65.89 7.65 4.53 Cl=11.56      16 CH.sub.3 H     ##STR101##      100° C. at0.2 m.m. Hg C.sub.18 H.sub.35 NO.sub.2 72.68 11.68     4.71 72.53 11.96 4.50      17 CH.sub.3  H     ##STR102##      65° C at0.4 m.m. Hg. C.sub.13 H.sub.23 NO.sub.2 69.29 10.29 6.22 6     9.64 10.30 6.15      18 CH.sub.3 H     ##STR103##      196° C at12 m.m. Hg C.sub.17 H.sub.25 NO.sub.2 74.14 9.15 5.09     74.35 9.23 5.13      19 CH.sub.3 H     ##STR104##      180° C at0.5 m.m. Hg C.sub.17 H.sub.31 NO.sub.2 72.55 11.10 4.98 7     2.84 11.04 4.77      20 CH.sub.3 H     ##STR105##      44° C  C.sub.28 H.sub.55 NO.sub.2 76.83 12.66 3.20 76.71 12.35     3.22      21 CH.sub.3 H     ##STR106##      116-17° C at0.2 m.m. Hg C.sub.18 H.sub.35 NO.sub.2 72.68 11.86     4.71 72.56 11.50 4.99      22 CH.sub.2CH . CH.sub.2 H     ##STR107##      0.05 m.m. Hg129-30° C at C.sub.17 H.sub.25 NO.sub.3 70.07 8.65     4.81 70.70 8.86 4.42      23 CH.sub.3 H     ##STR108##      41-2° C C.sub.30 H.sub.59 NO.sub.2 77.36 12.77 75.84 12.25  24      ##STR109##      H      ##STR110##      183- 5° C at 0.1 m.m. Hg C.sub.24 H.sub.39 NO.sub.2 77.16 10.52     3.75 77.43 10.39 3.54      25     ##STR111##      H      ##STR112##      55-6° C C.sub.34 H.sub.59 NO.sub.2 79.47 11.57 2.73 79.32 11.59     2.45      26 CH.sub.3 H     ##STR113##      174-8° C at0.1 m.m. Hg C.sub.22 H.sub.29 NO.sub.2 77.84 8.61     4.13 78.35 8.63 4.12  27 CH.sub.3      (CH.sub.2).sub.11 H     ##STR114##      190° C at0.05 m.m. Hg C.sub.29 H.sub.57 NO.sub.2 77.10 12.72     3.10 77.20 13.02 3.08      28 CH.sub.3 H     ##STR115##      69-70° C C.sub.24 H.sub.31 NO.sub.2 78.87 8.55 3.83 79.38 8.80     3.69      29 CH.sub.3 H     ##STR116##      90° C at0.1 m.m. Hg C.sub.15 H.sub.29 NO.sub.2 70.54 11.45 5.48     69.99 11.24 5.25  30 CH.sub.3      (CH.sub.2).sub.11 H     ##STR117##      56° C C.sub.28 H.sub.46 NO.sub.2 Cl 72.60 9.90 3.02 Cl=7.66     71.98 10.19 3.01 Cl=7.35      31 CH.sub.3 H     ##STR118##      200° C at0.2 m.m. Hg C.sub.24 H.sub.47 NO.sub.2 S 69.70 11.45     3.39 69.69 11.48 3.31       32 CH.sub.3 H     ##STR119##      119° C C.sub.21 H.sub.35 NO.sub.2 75.63 10.58 4.20 75.94 10.30     3.93          33 CH.sub.3      (CH.sub.2).sub.17 H     ##STR120##      Purified bychromatography C.sub.34 H.sub.59 NO.sub.2 MOLECULAR WEIGHT =     513FOUND (FROM MASS SPECTROMETRY =      513)

EXAMPLE 34

A solution of 17.10 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol in 50parts of dry benzene was stirred at 15°-20° C. whilst adding 6.0 partsof sebacoyl chloride dropwise over 15 minutes. The mixture was stirredfor a further 12 hours at room temperature after which the1,2,2,6,6-pentamethylpiperidin-4-ol hydrochloride formed during thereaction was filtered off. The benzene was removed by distillation underreduced pressure to give a yellow oil, which was distilled under reducedpressure to give bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate as acolorless oil having a boiling point of 218°-20° C. at 0.4 mm of Hg andthe following elemental analysis by weight:

    ______________________________________                                                Found   Required  (for C.sub.30 H.sub.56 N.sub.2 O.sub.4)             ______________________________________                                        Carbon    70.99 %   70.82 %                                                   Hydrogen  10.97 %   11.10 %                                                   Nitrogen  5.26 %    5.51 %                                                    ______________________________________                                    

Table 2 gives a list of esters prepared using the procedure of Example34.

                                      TABLE 2                                     __________________________________________________________________________                             m.p. or        ANALYSIS                              __________________________________________________________________________    Ex-                      b.p.    Molecular                                                                            Required (%)                                                                             Found                      __________________________________________________________________________                                                       (%)                        ample   R.sub.1                                                                          R.sub.2                                                                         R.sub.3     ° C. at m.m.                                                                   Formula                                                                              C   H   N  C   H   N                  __________________________________________________________________________     35      CH.sub.3                                                                         H                                                                               ##STR121##  Purified by chromatography                                                            C.sub.26 H.sub.42 N.sub.2 O.sub.4                                                            5.86       5.64               36      CH.sub.3                                                                         H                                                                               ##STR122##  118° C.                                                                        C.sub.22 H.sub.40 N.sub.2 O.sub.4                                                    66.63                                                                             10.17                                                                             7.06                                                                             66.94                                                                             10.22                                                                             6.95               37      CH.sub.3                                                                         H                                                                               ##STR123##  123° C.                                                                         C.sub.28 H.sub.44 N.sub.2 O.sub.4                                                   70.15                                                                             9.38                                                                              5.93                                                                             70.75                                                                             9.68                                                                              5.69               38      CH.sub.3                                                                         H                                                                               ##STR124##  75-6° C.                                                                       C.sub.21 H.sub.27 NO.sub.2                                                           77.50                                                                             8.36                                                                              4.30                                                                             77.78                                                                             8.45                                                                              4.06               39      CH.sub.3                                                                         H                                                                               ##STR125##  138° C. at 12 m.m. Hg.                                                         C.sub.12 H.sub.23 NO.sub.2                                                           67.57                                                                             10.87                                                                             6.57                                                                             67.90                                                                             10.72                                                                             6.53               40      CH.sub.3                                                                         H                                                                               ##STR126##  142° C.                                                                        C.sub.25 H.sub.41 NO.sub.3                                                           74.40                                                                             10.24                                                                             3.47                                                                             74.80                                                                             9.99                                                                              3.43              __________________________________________________________________________

example 41

a mixture of 17.10 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol, 13.60parts of methyl benzoate and 2.0 parts of lithium amide was heated at160° C. for 6 hours with removal of the methyl alcohol formed bydistillation. Water pump vacuum was applied and heating continued for afurther two hours; on cooling the residue was dissolved in chloroformand filtered to remove the lithium amide. The chloroform was removed bydistillation under reduced pressure to give a yellow oil which wasfractionally distilled under reduced pressure to yield 6.40 parts of1,2,2,6,6-pentamethylpiperidinyl-4-benzoate having a boiling point of126° C. at 0.1 mm of Hg. and the following elemental analysis by weight:

    ______________________________________                                                Found   Required  (for C.sub.17 H.sub.25 NO.sub.2)                    ______________________________________                                        Carbon    74.35 %   74.14 %                                                   Hydrogen  9.23 %    9.15 %                                                    Nitrogen  5.13 %    5.09 %                                                    ______________________________________                                    

EXAMPLE 42

A mixture of 17.10 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol, 14.60parts of methyl-β-(3,5-di-t-butyl-4-hydroxyphenyl) propionate and 1.0part of lithium amide was heated together to 130° C. Water pump vacuumwas then applied to the reaction mixture whilst maintaining thetemperature at 125°-135° C. for 3 hours.

The temperature of the reaction mixture was then raised to 160° C. andhigh vacuum (0.5-1 mm Hg) was applied for 1 hour. The reaction mixturewas cooled, dissolved in chloroform and filtered. Removal of thechloroform by distillation under reduced pressure gave a brown oilwhich, when triturated with ether, gave a white solid which wascollected by filtration, washed well with ether and dried to give 16.0parts of1,2,2,6,6-pentamethylpiperidinyl-4-β-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate as its bicarbonate salt having a melting point of 210°-11°C., and the following elemental analysis by weight:

    ______________________________________                                                Found   Required  (for C.sub.28 H.sub.47 NO.sub.6)                    ______________________________________                                        Carbon    68.90 %   68.10 %                                                   Hydrogen  9.56 %    9.60 %                                                    Nitrogen  2.91 %    2.84 %                                                    ______________________________________                                    

EXAMPLE 43

15.0 parts of the product from Example 2 were dissolved in water andneutralised with sodium hydroxide solution. The aqueous solution wasextracted with ether, the combined ether extracts were dried overanhydrous magnesium sulphate. The ether was removed by distillationunder reduced pressure to give a white solid which was recrystallisedfrom ethanol to give 9.30 parts of1,2,2,6,6-pentamethylpiperidinyl-4-β-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate having a melting point of 124°-5° C. and the followingelemental analysis by weight:

    ______________________________________                                                Found   Calculated                                                                              (for C.sub.27 H.sub.45 NO.sub.3)                    ______________________________________                                        Carbon    75.00     75.30                                                     Hydrogen  10.50     10.20                                                     Nitrogen  3.50      3.30.                                                     ______________________________________                                    

EXAMPLE 44

A mixture of 10.26 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol, 5.04parts of trimethyl trimesate and 0.20 parts of lithium amide in 100parts of xylene was heated at 137° C. for 7 hours. The methyl alcoholformed during the reaction being removed by distillation. The cooledreaction mixture was filtered to remove the lithium amide and the xylenesolvent removed by distillation under reduced pressure. Purification ofthe residue by preparative thin layer chromatography yieldeddimethyl(1,2,2,6,6-pentamethylpiperidinyl-4) trimesate having thefollowing molecular weight:

    ______________________________________                                        Found (from mass spectrometry)                                                                          391                                                 Required (for C.sub.21 H.sub.29 NO.sub.6)                                                               391                                                 ______________________________________                                    

and methylbis(1,2,2,6,6-pentamethylpiperdinyl-4) trimesate having thefollowing molecular weight:

    ______________________________________                                        Found (from mass spectrometry)                                                                          530                                                 Required (for C.sub.30 H.sub.46 N.sub.2 O.sub.6)                                                        530.                                                ______________________________________                                    

EXAMPLE 45

A mixture of 16.4 parts of 1,2,2,6,6-pentamethyl-piperidin-4-ol, 6.27parts of methyl isocyanate and 0.5 parts of1,4-diazabicyclo[2,2,2]octane was refluxed in 150 parts of dry benzenefor 24 hours. Removal of the benzene solvent by distillation underreduced pressure yielded an oily solid which was poured on to 200 partsof water and allowed to stand for 24 hours. The solid formed wascollected by filtration, dried and crystallised from n-hexane to give14.2 parts of 4-methylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidinehaving a melting point of 96°-7° C. and the following elemental analysisby weight:

Table 3 gives a list of carbamoyloxy esters prepared using the procedureof Example 45.

    ______________________________________                                                Found   Required  (for C.sub.12 H.sub.24 N.sub.2 O.sub.2)             ______________________________________                                        carbon    63.28 %   63.12 %                                                   hydrogen  10.70 %   10.59 %                                                   nitrogen  12.09 %   12.27 %                                                   ______________________________________                                    

    TABLE 3      m.p. or ANALYSIS  Ex- b.p. Molecular Required (%) Found (%)        ample R.sub.1 R.sub.2 R.sub.3 ° C. at m.m. Formula C H N C H     N                 46 CH.sub.3 H      ##STR127##      63° C. C.sub.17 H.sub.34 N.sub.2 O.sub.2 68.41 11.48 9.39 68.17     11.32 9.16      47 CH.sub.3 H     ##STR128##      56-7° C. C.sub.29 H.sub.58 N.sub.2 O.sub.2 74.62 12.52 6.00     74.58 12.34 5.96      48 CH.sub.3 H     ##STR129##      62° C. C.sub.14 H.sub.26 N.sub.2 O.sub.2 66.11 10.30 11.01 66.40 1     0.27 10.92      49 CH.sub.3 H     ##STR130##      184-6° C. at 2 m.m. Hg. C.sub.17 H.sub.32 N.sub.2 O.sub.2 68.88     10.889.45 68.98 10.84 9.43      50 CH.sub.3 H     ##STR131##      109-10° C. C.sub.17 H.sub.26 N.sub.2 O.sub.2 70.31 9.02 9.65     70.61 8.80 9.53      51 CH.sub.3 H     ##STR132##      106-7° C. C.sub.18 H.sub.28 N.sub.2 O.sub.2 71.02 9.27 9.20     71.42 9.41 9.02      52 CH.sub.3 H     ##STR133##      121° C. C.sub.17 H.sub.25 N.sub.2 O.sub.2 Cl 62.86 7.70 8.68     62.92 7.75 8.87      53 CH.sub.3 H     ##STR134##      129° C. C.sub.21 H.sub.28 N.sub.2 O.sub.2 74.08 8.29 8.23 74.37     8.07 8.41      54 CH.sub.3 H     ##STR135##      101-4° C. C.sub.28 H.sub.54 N.sub.4 O.sub.4 65.84 10.66 10.97     65.86 10.40 10.64      55 CH.sub.3 H     ##STR136##      163-5° C C.sub.29 H.sub.48 N.sub.4 O.sub.4 67.41 9.36 10.84     67.21 9.52  10.83      56 CH.sub.3 H     ##STR137##      183° C C.sub.35 H.sub.52 N.sub.4 O.sub.4 70.91 8.84 9.45 70.64     8.79 9.24      ##STR138##      57 CH.sub.3 H     ##STR139##      178° C C.sub.32 H.sub.48 N.sub.4 O.sub.4 69.53 8.75 10.14 70.39     8.71 9.86      58 CH.sub.2CH . CH.sub.2 H     ##STR140##      165° C at 0.05 m.m. Hg C.sub.19 H.sub.34 N.sub.4 O.sub.4 70.76     10.63 8.69 70.64 10.80 9.04      59 CH.sub.2CH . CH.sub. 2 H     ##STR141##       60 CH.sub.3 CH.sub.2      CH.sub.2 H     ##STR142##      61     ##STR143##      H      ##STR144##

EXAMPLE 62

A mixture of 28.3 parts of 2,2,6,6-tetramethyl-4-piperidinyl-n-octanoateand 8.55 parts of benzyl bromide was stirred and heated at 105° C. for72 hours. Ether was added to the cooled reaction mixture and the2,2,6,6-tetramethyl-4-piperidinyl-n-octanoate hydrobromide formed duringthe reaction was filtered off. The ether solvent was removed bydistillation under reduced pressure and the residue distilled underrediced pressure to give 16.40 parts of1-benzyl-2,2,6,6-tetramethyl-4-piperidinyl-n-octanoate having a boilingpoint of 180° C. at 0.1 mm of Hg and the following elemental analysis byweight:

    ______________________________________                                                Found   Required  (for C.sub.24 H.sub.29 NO.sub.2)                    ______________________________________                                        Carbon    77.46 %   77.16 %                                                   Hydrogen  10.50 %   10.52 %                                                   Nitrogen  3.86 %    3.75 %                                                    ______________________________________                                    

Table 4 gives a list of esters prepared using the procedure of Example62.

                                      TABLE 4                                     __________________________________________________________________________    Ex-                      m.p. or        ANALYSIS                              __________________________________________________________________________    ample                    b.p.    Molecular                                                                            Required (%)                                                                              Found                     __________________________________________________________________________                                                        (%)                       No. R.sub.1  R.sub.2                                                                         R.sub.3   ° C at m.m.                                                                    Formula                                                                              C   H   N    C  H   N                 __________________________________________________________________________     63                                                                                ##STR145##                                                                             H                                                                               ##STR146##                                                                              98-9° C                                                                        C.sub.42 H.sub.64 N.sub.2 O.sub.4                                                    76.32                                                                             9.76                                                                              4.24                                                                              76.04                                                                             9.49                                                                              4.04              64                                                                                ##STR147##                                                                             H                                                                               ##STR148##                                                                              191-2° C at 0.1 m.m. Hg                                                        C.sub.21 H.sub.31 NO.sub.5                                                           66.82                                                                             8.28                                                                              3.71                                                                              66.81                                                                             8.52                                                                              3.84               65                                                                               CH.sub.2CHCH.sub.2                                                                     H                                                                               ##STR149##                                                                              142-4° C at 0.2 m.m. Hg                                                        C.sub.20 H.sub.37 NO.sub.2                                                           74.25                                                                             11.53                                                                             4.33                                                                              74.06                                                                             11.36                                                                             4.32              66  CHC . CH.sub.2                                                                         H                                                                               ##STR150##                                                                              68-9° C                                                                        C.sub.20 H.sub.27 NO.sub.3                                                           72.92                                                                             8.26                                                                              4.25                                                                              72.82                                                                             8.28                                                                              4.55              67  CH.sub.2CHCH.sub.2                                                                     H                                                                               ##STR151##                                                                              150° C at  0.05 m.m. Hg                                                        C.sub.19 H.sub.27 NO.sub.2                                                           75.71                                                                             9.03                                                                              4.65                                                                              75.58                                                                             9.25                                                                              4.45              68  CH.sub.2CHCH.sub.2                                                                     H                                                                               ##STR152##                                                                              250° C at  0.5 m.m. Hg                                                         C.sub.34 H.sub.60 N.sub.2 O.sub.4                                                    72.81                                                                             10.78                                                                             4.99                                                                              73.07                                                                             10.60                                                                             4.77              69  COH.sub.2CH . CH.sub.2                                                                 H                                                                               ##STR153##                                                                              139-42° C at 0.2 m.m. Hg                                                       C.sub.19 H.sub.33 NO.sub.3                                                           70.55                                                                             10.28                                                                             4.33                                                                              70.37                                                                             10.38                                                                             4.39             __________________________________________________________________________

example 70

a mixture of 17.10 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol and 3.50parts of metallic sodium in 125 parts of toluene was heated under refluxconditions for 24 hours. The toluene solution was decanted off from theexcess sodium and then refluxed for a further 24 hours with 36.60 partsof n-octadecyl bromide. The cooled solution was filtered to remove thesodium bromide which was formed during the reaction and the toluenesolvent was removed by distillation under reduced pressure. Fractionaldistillation of the residue gave4-octadecyloxy-1,2,2,6,6-pentamethylpiperidine having a boiling point of184° C. at 0.25 m.m. of Hg. and the following elemental analysis byweight:

    ______________________________________                                                Found   Required  (for C.sub.28 H.sub.57 NO)                          ______________________________________                                        Carbon    78.66 %   79.36%                                                    Hydrogen  13.77 %   13.56 %                                                   Nitrogen  2.99 %    3.31 %                                                    ______________________________________                                    

Table 5 gives a list of ethers prepared using the procedure of Example70.

                                      TABLE 5                                     __________________________________________________________________________    Ex-                  m.p. or        ANALYSIS                                  __________________________________________________________________________    ample                b.p.    Molecular                                                                            REQUIRED(%)                                                                              FOUND(%)                       __________________________________________________________________________    No.   R.sub.1                                                                          R.sub.2                                                                         R.sub.3   ° C at m.m. Hg.                                                                Formula                                                                              C   H   N  C   H   N                      __________________________________________________________________________    71    CH.sub.3                                                                         H CH.sub.2 CH . CH.sub.2                                             72    CH.sub.3                                                                         H                                                                                ##STR154##                                                        73    CH.sub.3                                                                         H CH.sub.3 (CH.sub.2).sub.11                                         74    CH.sub.3                                                                         H (CH.sub.2).sub.4                                                                        m.p. 62-63                                                                            C.sub.24 H.sub.48 N.sub.2 U.sub.2                                                    72.74                                                                             12.09                                                                             7.07                                                                             73.00                                                                             11.94                                                                             6.85                   75    CH.sub.3                                                                         H (HCCH.sub.2                                                                             b.p. 0,3 mm                                                                           C.sub.13 H.sub.23 NO                                                                 74.59                                                                             11.07                                                                             6.69                                                                             74.48                                                                             10.95                                                                             6.41                                        73-74                                                    76    CH.sub.3                                                                         H CH.sub.3 (CH.sub.2).sub.3                                                               b.p. 19 mm                                                                            C.sub.14 H.sub.29 NO                                                                 73.95                                                                             12.85                                                                             6.16                                                                             74.05                                                                             12.93                                                                             6.10                                        123-124                                                  __________________________________________________________________________

example 77

3.23 parts of 1-allyl-2,2,6,6-tetramethyl-4-piperidinyl-t-n-octanoate in50 parts of ethyl alcohol was hydrogenated at room temperature and 1atmosphere pressure using 0.1 parts of 5% palladium on charcoal as thecatalyst. The reaction mixture was filtered to remove the catalyst andthe ethyl alcohol removed by distillation under reduced pressure to give2.90 parts of 1-n-propyl-2,2,6,6-tetramethyl-4-piperidinyl-n-octanoatehaving a boiling point of 128° C. at 0.05 mm of Hg and the followingelemental analysis by weight:

    ______________________________________                                                Found   Required  (for C.sub.20 H.sub.39 NO.sub.2)                    ______________________________________                                        Carbon    73.50 %   73.79 %                                                   Hydrogen  12.26 %   12.08 %                                                   Nitrogen  4.31 %    4.30 %                                                    ______________________________________                                    

Table 6 gives a list of compounds prepared using the procedure ofExample 77.

                                      TABLE 6                                     __________________________________________________________________________                                    ANALYSIS                                                           m.p. or                                                  Example              b.p. Molecular                                                                           REQUIRED (%)                                                                          FOUND (%)                             No.  R.sub.1                                                                              R.sub.2                                                                         R.sub.3                                                                              ° C m.m.                                                                    Formula                                                                             C H  N  C H N                                 __________________________________________________________________________    78   CH.sub.3 CH.sub.2 CH.sub.2--                                                         H CH.sub.3 CH.sub.2 CH.sub. 2--                                   79   CH.sub.3                                                                             H CH.sub.3 CH.sub.2 CH.sub. 2--                                   __________________________________________________________________________

EXAMPLE 80

a. A mixture of 2.83 parts of2,2,6,6-pentamethyl-4-piperidinyl-n-octanoate and 1.50 parts by volumeof liquid ethylene oxide was charged into a 50 ml autoclave previouslycooled to -50° C. A pressure of 100 atmospheres of nitrogen was appliedand the autoclave heated at 200° C., with stirring, for three hours.Fractional distillation of the cooled reaction mixture yielded 2.30parts of1-(2'-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl-n-ocyanoate havinga boiling point of 186°-7° C. at 0.25 mm of Hg and the followingelemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.19 H.sub.37 NO.sub.3)                         ______________________________________                                        Carbon     69.93 %       69.68 %                                              Hydrogen   11.09 %       11.39 %                                              Nitrogen   4.37 %        4.28 %                                               ______________________________________                                    

b. A mixture of 11.32 parts of2,2,6,6-tetramethyl-4-piperidinyl-n-octanoate -and 2.50 parts of2-bromoethanol was stirred at 100° C. for 65 hours. Petroleum ether (bp40°-60° C.) was added to the cooled reaction mixture and the2,2,6,6-tetramethylpiperidinyl-4-n-octanoate hydrobromide formed duringthe reaction was filtered off. The petroleum ether solvent was removedby distillation under reduced pressure and the residue distilled toyield 1-(2'-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl-n-octanoatehaving a boiling point of 176° C. at 0.2 mm of Hg. This sample wasidentical to that prepared under Example 80a.

EXAMPLE 81

A mixture of 11.45 parts of4-phenylcarbamoyloxy-2,2,6,6-tetramethylpiperidine and 60 parts ofstyrene ocide in 60 parts of n-hexanol was heated under refluxconditions for 18 hours. The n-hexanol solvent and unreacted styreneoxide were removed by distillation under reduced pressure to yield apale yellow crystalline solid. Purification by trituration with hotpetroleum ether (b.p. 60°-80° C.) yielded4-phenylcarbamoyloxy-1-[2'-hydroxy-2'-phenylethyl]-2,2,6,6-tetramethylpiperidinehaving a melting point of 186°-7° C. with the following elementalanalysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.24 H.sub.32 N.sub.2 O.sub.3)                  ______________________________________                                        Carbon     72.51 %       72.70 %                                              Hydrogen   7.92 %        8.13 %                                               Nitrogen   6.91 %        7.06 %                                               ______________________________________                                    

EXAMPLE 82

A mixture of 5.61 parts of 2,2,6,6-tetramethyl-4-piperidin-n-octanoateand 5.0 parts of propylene oxide were charged to an autoclave. Apressure of 100 atmospheres nitrogen was applied. The mixture was heatedat 200° C. for 3 hours. Fractionation under reduced pressure gave a mainfraction b.p. 160°-183° C. at 0.1 mm. which after passing down analumina type H column eluting with chloroform yielded a pale yellowsemi-solid1-(2'-hydroxypropyl)-2,2,6,6-tetramethyl-4-piperidin-n-octanoate havingthe following elemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.20 H.sub.39 NO.sub.3)                         ______________________________________                                        Carbon     70.20 %       70.34 %                                              Hydrogen   11.45 %       11.51 %                                              Nitrogen   3.89 %        4.10 %                                               ______________________________________                                    

EXAMPLE 83

A mixture of 3.27 parts of the product from Example 80 a., 0.60 parts ofacetic acid and 0.1 parts of tetra-n-butyl titanate in 40 parts ofxylene was heated under reflux conditions for 24 hours. The xylenesolvent was removed by distillation under reduced pressure and theresidue fractionally distilled to give1-(2'-acetoxyethyl)2,2,6,6-tetramethyl- 4-piperidinyl-n-octanoate havinga boiling point of 190°-2° C. at 1 m.m. Hg and the following elementalanalysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.21 H.sub.39 NO.sub.4)                         ______________________________________                                        Carbon     68.17 %       68.25 %                                              Hydrogen   10.65 %       10.64 %                                              Nitrogen   3.36 %        3.79 %                                               ______________________________________                                    

EXAMPLE 84

A mixture of 3.27 parts of the product from Example 78 a., 0.63 parts ofmethyl isocyanate and 0.1 parts of 1,4-diazabicyclo[2,2,2] octane in 30parts of dry benzene was heated under reflux conditions for 24 hours.The benzene solvent was removed by distillation under reduced pressureand the residue crystallised from aqueous ethyl alcohol to give1-(2'-methylcarbamoyloxyethyl)-2,2,6,6-tetramethyl-4-piperidinyl-n-octanoatehaving a melting point of 61°-3° C. and the following elemental analysisby weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.21 H.sub.40 N.sub.2 O.sub.4)                  ______________________________________                                        Carbon     65.72 %       65.59 %                                              Hydrogen   10.37 %       10.48 %                                              Nitrogen   7.11 %        7.28 %                                               ______________________________________                                    

EXAMPLE 85

A mixture of 3.0 parts of the product from Example 81, 0.90 parts ofphenyl isocyanate and 0.1 parts of 1,4-diazabicyclo[2,2,2]octane in 25parts of dry benzene was heated under reflux conditions for 24 hours.The benzene solvent was removed by distillation under reduced pressureand the residue crystallised from petroleum ether (b.p. 60°-80° C.) togive4-phenylcarbamoyloxy-1-[2'-(phenylcarbamoyloxy)2'-phenylethyl]-2,2,6,6-tetramethylpiperidinehaving a melting point of 173° C. and the following elemental analysisby weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.31 H.sub.37 N.sub.3 O.sub.4)                  ______________________________________                                        Carbon     72.65 %       72.21 %                                              Hydrogen   7.22 %        7.23 %                                               Nitrogen   7.97 %        8.15 %.                                              ______________________________________                                    

EXAMPLE 86

A mixture of 3.14 parts of 2,2,6,6-tetramethylpiperidin-4-ol and 3.50parts of acetic anhydride was heated on a steam bath for one hour. Afterthis time 20 parts of water were added and heating continued for afurther one hour. The solution was carefully neutralised with asaturated solution of sodium bi-carbonate and then ether extracted. Thecombined ether extracts were washed twice with 5 % sodium bi-carbonatesolution and twice with brine, the ether solution was then dried overanhydrous magnesium sulphate and the ether removed by distillation underreduced pressure to yield1-acetyl-2,2,6,6-tetramethyl-piperidinyl-4-acetate having a meltingpoint of 33°-4° C. and the following elemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.13 H.sub.23 NO.sub.3)                         ______________________________________                                        Carbon     64.51 %       64.73 %                                              Hydrogen   9.69 %        9.54 %                                               Nitrogen   5.67 %        5.81 %                                               ______________________________________                                    

EXAMPLE 87

A mixture of 15.70 parts of 2,2,6,6-tetramethylpiperidin-4-ol, 22.80parts of methyl isocyanate and 0.5 parts of1,4-diazabicyclo[2,2,2]octane in 100 parts of dry benzene was heatedunder reflux conditions for 24 hours. The benzene solvent was removed bydistillation under reduced pressure and 150 parts of water added to theresidue which was stood overnight at room temperature. The solid formedwas collected by filtration and dried to yield 19.60 parts of a whitecrystalline solid having a melting point of 167°-8° C. This solid wasshown to contain 80 % of4-methylcarbamoyl-1-methylcarbamoyl-2,2,6,6-tetramethylpiperidine frommicroanalysis and nuclear magnetic resonance spectra.

EXAMPLE 88

a. 2.65 parts of acrylonitrile was added dropwise with stirring to asolution of 8.55 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol and 0.30parts of 40 % potassium hydroxide solution in 80 parts of benzene.Stirring was continued at room temperature for 16 hours after which timethe solution was washed with water, dried and the benzene solventremoved by distillation under reduced pressure. Fractional distillationof the residue, under reduced pressure gave 1.70 parts of4-(2'-cyanoethoxy)-1,2,2,6,6-pentamethylpiperidine having a boilingpoint of 105°-6° C. at 0.1 mm of Hg and the following elemental analysisby weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.13 H.sub.24 N.sub.2 O)                        ______________________________________                                        Carbon     69.27 %       69.60 %                                              Hydrogen   10.69 %       10.78 %                                              Nitrogen   12.40 %       12.49 %.                                             ______________________________________                                    

b. To 51 parts of 1,2,2,6,6-pentamethylpiperidine-4-ol a solution ofmetallic sodium in two parts of tert.butanol was added. 52.5 parts ofacrylonitrile was dropped in with rapid stirring. After standing for twodays at room temperature the mixture was heated to 80° C. for 2 hoursand distilled under reduced pressure yielding 4-(2'-cyanoethoxy)1,2,2,6,6-pentamethylpiperidine with a boiling point of 172°-4° C. at 17mm Hg. This sample was identical to that prepared under Example 88a.

EXAMPLE 89

A misture of 13.0 parts of 4-dodecyloxy-2,2,6,6-tetramethylpiperidineand 3.42 parts of benzyl bromide was heated at 100° C. for 48 hours.Petroleum ether (b.p. 40°-60° C. was added to the cooled reactionmixture and the 4-dodecyloxy-2,2,6,6-tetramethylpiperidine hydrobromideformed during the reaction was filtered off. The petroleum ether solventwas removed by distillation under reduced pressure and the residuefractionally distilled to give4-dodecyloxy-1-benzyl-2,2,6,6-tetramethylpiperidine having a boilingpoint of 200° C. at 0.5 m.m. of Hg. and the following elemental analysisby weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.28 H.sub.49 NO)                               ______________________________________                                        Carbon     80.67 %       80.90 %                                              Hydrogen   11.82 %       11.88 %                                              Nitrogen   3.34 %        3.37 %                                               ______________________________________                                    

EXAMPLE 90

A mixture of 4-benzyloxy-2,2,6,6-tetramethylpiperidine and 1.67 parts ofethyl α-bromoacetate in 30 parts of ethyl alcohol was heated underreflux conditions for 115 hours. The ethyl alcohol solvent was removedby distillation under reduced pressure and the residue fractionallydistilled to give4-benzyloxy-1-ethoxycarbonylmethyl-2,2,6,6-tetramethylpiperidine havinga boiling point of 145°-6° C at 0.2 m.m. of Hg. and the followingelemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.20 H.sub.39 NO.sub.3)                         ______________________________________                                        Carbon     71.62 %       72.04 %                                              Hydrogen   8.90 %        9.37 %                                               Nitrogen   3.94 %        4.20 %                                               ______________________________________                                    

EXAMPLE 91

A mixture of 25.7 parts of 1,2,2,6,6-pentamethyl-piperidin-4-ol and 3.09parts of boric acid in 100 parts of toluene was heated under refluxconditions with azeotropic removal of water for 24 hours. The toluenesolvent was removed by distillation under reduced pressure to givetris-(1,2,2,6,6-pentamethyl-4-piperidinyl)borate having a melting pointof 83°-9° C. and the following elemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.30 H.sub.60 N.sub.3 O.sub.3 B)                ______________________________________                                        Carbon     68.85 %       69.05 %                                              Hydrogen   11.68 %       11.59 %                                              Nitrogen   7.76 %        8.06 %                                               ______________________________________                                    

EXAMPLE 92

30 parts of 1,2,2,6,6-pentamethylpiperidin-4-ol were dissolved in 250parts of benzene and 4 parts of sodium added. The solution was heatedovernight at reflux temperature and then cooled. 38 parts of2-phenoxyethanol tosylate were added dropwise and the solution heated atreflux for 5 hours. On cooling the precipitate was filtered off and thefiltrate evaporated in vacno. Treatment of the residue with dilutehydrochloric acid and then basification with dilute sodium hydroxide toa pH 10 was followed by extraction with ether. Evaporation afforded apale yellow oil which was chromatographed on alumina to give4-(2'-phenoxyethoxy)1,2,2,6,6-pentamethylpiperidine as a colourless oilwhich gave the following elemental analysis by weight:

    ______________________________________                                                             Required                                                          Found       (for C.sub.18 H.sub.29 NO.sub.2)                         ______________________________________                                        Carbon     72.49 %       74.18 %                                              Hydrogen   9.89 %        10.03 %                                              Nitrogen   4.91 %        4.81 %                                               ______________________________________                                    

EXAMPLE 93

A mixture of 9.87 parts of 4-allyloxy-2,2,6,6-tetramethylpiperidine and3.03 parts of allyl bromide was heated at 90° C. for 96 hours. Ether wasadded to the cooled reaction mixture and the4-allyloxy-2,2,6,6-tetramethylpiperidine hydrobromide formed during thereaction was filtered off. The ether solvent was removed by distillationunder reduced pressure and the residue purified by chromatography togive 4-allyloxy-1-allyl-2,2,6,6-tetramethylpiperidine.

EXAMPLES 94 - 116 Testing in polypropylene film

38 parts of polypropylene were homogenised with 0.076 parts ofn-octadecyl-β(4'-hydroxy-3',5'-t-butylphenyl) propionate in a kneadingmachine over a period of 3 minutes at 200° C. 0.19 parts of the productof Example 13 was then added and homogenisation continued for another 7minutes.

This composition was compression moulded into films of 0.1 mm thicknessat 260° C. for 6 minutes and the films so obtained were then quenched incold water.

A section measuring 44 × 100 mm was separated from the 0.1 mm annealedpolypropylene foil and exposed to light irradiation in a fademeterdevice consisting of a circular bank of 28 alternate sunlight andblacklight lamps. The sunlight lamps were 2 feet long, 20-wattfluorescent lamps characterised by a peak emission of 3,100 Angstromunits; the blacklight lamps were 2 feet long, 20-watt ultraviolet lampscharacterised by a peak emission of 3,500 Angstrom units. The sample wasrotated concentrically about the bank of lamps so that the radiationtherefrom was uniformly distributed over the section under test.

The exposed sample was examined periodically and portions of it testedfor the percent/elongation at break, the time at which the samplereached 50 % of the initial elongation at break was noted.

Similar tests were carried out on polypropylene samples containing,respectively, no stabiliser and known stabilisers, and also stabilisersfalling within the scope of German Patent Specification No. 1,929,928.The results obtained are set out in the following table:

                                      TABLE                                       __________________________________________________________________________                                             Factor                                                                        Time to 50% of initial                                                        elongation at break                                                           (additive)                                                                    Time to 50% of initial                                                        elongation at break                  Example                                                                            Additive                            (control)                            __________________________________________________________________________    --   none                                1.0                                  --   2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole                                                       3.2                                  --   4-phenylcarbamoyloxy-2,2,6,6-tetramethylpiperidine                                                                1.8                                  --   1,6-bis[4'-carbamoyloxy-2',2',6',6'-tetramethylpiperidine]hexane                                                  2.4                                  --   2,2,6,6-tetramethylpiperidinyl-4-benzoate                                                                         2.6                                  --   bis(2,2,6,6-tetramethyl-4-piperidinyl)sebacate                                                                    4.7                                   94  1,2,2,6,6-pentamethylpiperidinyl-4-phenylacetate                                                                  5.2                                   95  bis(1,2,2,6,6-pentamethyl-4-piperidinyl)terephthalate                                                             5.3                                   96  1,2,2,6,6-pentamethylpiperidinyl-4-(p-methoxybenzoate)                                                            5.3                                   97  1,2,2,6,6-pentamethylpiperidinyl-4-(1'-naphthoate)                                                                5.4                                   98  1,2,2,6,6-pentamethylpiperidinyl-4-octanoate                                                                      6.2                                   99  1,2,2,6,6-pentamethylpiperidinyl-4-isobutyrate                                                                    6.2                                  100  bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate                                                                  8.0                                  101  2,4-bis(4'-carbamoyloxy-1',2',2',6',6'-pentamethylpiperidine)toluene                                              5.2                                  102  4-p-tolylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine                                                             5.2                                  103  4-allylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine                                                               5.5                                  104  4-phenylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine                                                              5.6                                  105  4-methylcarbamoyloxy-1,2,2,6,6-pentamethylpiperidine                                                              5.8                                  106  1,6-bis[4'-carbamoyloxy-1',2',2',6',6'-pentamethylpiperidine]hexane                                               9.2                                  107  bis(1-benzyl-2,2,6,6-tetramethyl-4-piperidinyl)sebacate                                                           5.0                                  108  1-ethoxycarbonylmethyl2,2,6,6-tetramethylpiperidinyl-4-(p-methoxy-                                                5.1                                       benzoate)                                                                109  1-benzyl-2,2,6,6-tetramethylpiperidinyl-4-(2'-ethylhexanoate)                                                     5.2                                  110  1-(n-dodecyl)-2,2,6,6-tetramethylpiperidinyl-4-octanoate                                                          5.2                                  111  1(2'-hydroxyethyl)-2,2,6,6-tetramethylpiperidinyl-4-octanoate                                                     5.8                                  112  1-(n-propyl)-2,2,6,6-tetramethylpiperidinyl-4-octanoate                                                           6.0                                  113  4-(n-dodecyloxy)-1,2,2,6,6-pentamethylpiperidine                                                                  5.5                                  114  4-(3'-cycanoethoxy)-1,2,2,6,6-pentamethylpiperidine                                                               >6.0                                 115  1,4-bis(1',2',2',6',6'-pentamethyl-4'-piperidinyloxy-)butane                                                      >6.0                                 116  Tris(1,2,2,6,6,pentamethyl-4-piperidinyl)borate                                                                   5.0                                  __________________________________________________________________________

EXAMPLES 117 to 119

The procedure described in Examples 94- 116 was repeated except that0.25% by weight of the light stabiliser under test was used, and,instead of polypropylene, a low-density polyethylene was employed assubstrate.

The pressing was conducted at 180° C. and the pressings werecompression-moulded into 1 mm. thick plaques at 150° C.

The plaques were stored at 20° C. and were periodically examinedvisually for the first sign of exudation.

The results obtained are summarized in the following Table which alsoincludes data relating to comparative experiments (known lightstabilisers added).

                  TABLE                                                           ______________________________________                                        Ex-                             Time to exudation                             ample        Light stabiliser added                                                                           (days)                                        ______________________________________                                        --    2,2,6,6-tetramethylpiperidinyl-                                                                     15                                                      4-stearate                                                              --    bis(2,2,6,6-tetramethyl-4-                                                                          20                                                      piperidinyl)sebacate                                                    --    4-stearylcarbamoyloxy-2,2,6,6-                                                                      13                                                      tetramethylpiperidine                                                   117   1,2,2,6,6-pentamethylpiperidinyl-                                                                   >50                                                     4-stearate                                                              118   bis(1,2,2,6,6-pentamethyl-4-                                                                        >50                                                     piperidinyl)sebacate                                                    119   4-stearylcarbamoyloxy-1,2,26,6-                                                                     >50                                                     pentamethylpiperidine                                                   ______________________________________                                    

EXAMPLES 120 to 122

The procedure described in Examples 117 to 119 was repeated except thatthe composition moulding was carried out at 200° C. and the substateused was highdensity polyethylene.

The results obtained are set out in the following Table, which alsocontains data relating to comparative experiments (using a known lightstabiliser).

                  TABLE                                                           ______________________________________                                        Ex-                             Time to exudation                             ample        Light Stabiliser   (days)                                        ______________________________________                                        --    2,2,6,6-tetramethylpiperidinyl-4-                                                                   40                                                      stearate                                                                120   1,2,2,6,6-pentamethylpiperidinyl-                                                                   >75                                                     4-stearate                                                              121   4-stearylcarbamoyloxy-1,2,2,6,6-                                                                    >75                                                     tetramethylpiperidine                                                   122   1-(n-dodecyl)-2,2,6,6-tetramethyl                                                                   >75                                                     piperidinyl-4-octaneate                                                 ______________________________________                                    

EXAMPLES 123 to 128

100 Parts of crystal polystyrene pellets were dry blended with 0.25 partof 1,2,2,6,6-pentamethylpiperidinyl-4-stearate, and the dry blend washomogenised by extension. The stabilised pellets so obtained wereinjection moulded to form plaques 2 mm. thick. These plaques wereexposed for 3000 hours in a "Xenotest 150" exposure unit, and anyyellowing of the plaques was measured by determining the yellownessfactor by means of the following equation: ##EQU1## wherein the Δ Tvalues represent the transmission loss of the sample at wavelengths of420 mm. and 680 mm. respectively, after exposure in the Xenotest unit,and T.sub.(560) represents the transmission value of an unexposed sampleat a wavelength of 560 mm.

The results obtained, as well as the results relating to a controlexperiment and other compositions of this invention are recorded in thefollowing Table.

                  TABLE                                                           ______________________________________                                                                       Yellowing                                                                     factor after                                   Example                                                                              Light stabiliser        3000 hours                                     ______________________________________                                        --     none                    35.0                                           123    1,2,2,6,6-pentamethylpiperidinyl-                                             4-stearate              10.0                                           124    1-benzyl-2,2,6,6-tetramethylpiperi-                                           dinyl-4-(2'-ethylhexanoate)                                                                           9.8                                            125    1,2,2,6,6-pentamethylpiperidinyl-                                      4-(n-octanoate)                                                                      9.5                                                                    126    4-(2'-cyanoethoxy)-1,2,2,6,6-penta-                                           methylpiperidine        8.0                                            127    4-stearylcarbamoyloxy-1,2,2,6,6-                                              pentamethylpiperidine   7.5                                            128    bis-(1,2,2,6,6-pentamethyl-4-                                                 piperidinyl)sebacate    6.6                                            ______________________________________                                    

EXAMPLES 129 to 132

25 parts by weight of a polyester-based film-forming polyurethane weredissolved in 75 parts by weight of a 1:1 mixture (by volume) ofdimethylformamide and acetone, and 1 % by weight of4(2'-cyanoethoxy)-1,2,2,6,6-pentamethylpiperidine was added.

The clear and homogeneous solution was drawn out on a glass plate to afilm of 400- 500 μ thickness, which was then dried as follows:

at 50° C. for 4 minutes

at 140° C. for 6 minutes

The final thickness of the film was 80- 100 μ.

The dried film samples were removed from the glass plate, mounted onwhite cardboard and exposed in a "Xenotest 450" exposure unit, one halfof the exposed sample being covered to facilitate subsequent visualestimation of yellowing due to exposure. The sample was controlled andrated visually at intervals of 100 hours.

The data obtained are set out in the following Table which also includesdata relating to a control experiment (no added light stabiliser) and toother experiments using stabilisers of this invention.

                  TABLE                                                           ______________________________________                                                                   Time to onset of                                   Example                                                                              Light Stabiliser    yellowing (hours)                                  ______________________________________                                        --     none                <100                                               129    4-(2'-cyanoethoxy)-1,2,2,6,6-                                                                     200                                                       pentamethylpiperidine                                                  130    1,2,2,6,6-pentamethyl-                                                                            300                                                       piperidinyl-4-octanoate                                                131    bis(1,2,2,6,6-pentamethyl-                                                                        300                                                       4-piperidinyl)sebacate                                                 132    4-phenylcarbamoyloxy-1-n-                                                                         400                                                       propyl-2,2,6,6-tetramethyl-                                                   piperidine                                                             ______________________________________                                    

EXAMPLES 133- 135

1000 Parts by weight of unstabilised polypropylene powder werethoroughly dry-blended with 1 part by weight ofn-octadecyl-β-(4'-hydroxy-3',5'-di-t-butylphenyl) propionate and 2 partsby weight of1,2,2,6,6-pentamethyl-4-piperidinyl-(3',5'-di-t-butyl-4'-hydroxy)benzoate. The dry-blend was extruded at cylinder temperatures of from180° to 220° C., and the resulting strand was granulated. The stabilisedformulation so obtained was melt-spun and stretched under the followingconditions:

    ______________________________________                                        Extruder temperatures     230/265/275° C.                              Melting temperature at the dye                                                                    :     270° C                                       Spinning speed      :     400 m./minute                                       Stretching Ratio    :     1 : 5                                               Titer of Multifilament                                                                            :     130/137 denier                                      Tensile Strength    :     6 g./denier                                         ______________________________________                                    

The multifilament obtained was mounted on a sample holder of a Xenotest150 apparatus (Quarzlampen GmbH) using white cardboard as backing. Inintervals of 200 hours of exposure time, 5 fibre samples are measuredfor their retained tensile strength. The data obtained are plottedagainst exposure time and the exposure time (T) to give 50% loss oforiginal tensile strength is derived from the graph. This value is takenas the failure time.

                                      TABLE                                       __________________________________________________________________________                                             Factor                               Example                    Time (T) to 50% retained                                                                    T stabilizer                         No.  Light Stabiliser      tensile strength                                                                            T control                            __________________________________________________________________________    none none                    430         1.0                                       2-(2'-hydroxy-3',5'-di-t-butylphenyl)                                                                 530         1.2                                  5-chlorobenzotriazole                                                         133  1,2,2,6,6-Pentamethyl-4-piperidinyl                                                                 1,400         3.3                                  (3',5'-di-t-butyl-4'-hydroxy                                                       benzoate)                                                                134  1,2,2,6,6-Pentamethyl-4-piperidinyl-β-                                                         1,600         3.7                                       (3',5'-di-t-butyl-4'-hydroxyphenyl)                                           propionate                                                               135  Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)                                                            2,600         6.0                                       sebacate                                                                 __________________________________________________________________________

EXAMPLES 136 to 144

The procedure described in Examples 94 to 116 was repeated except thatthe annealed polypropylene specimens were exposed to light irradiationin a Xenotest 450 exposure unit rather than in the fademeter device.

The results obtained are summarised in the following Table which alsoincludes data relating to a control experiment (no added lightstabiliser) and a comparative experiment (a known light stabiliseradded).

                  TABLE                                                           ______________________________________                                                                        Time to                                       Ex-                             Failure                                       ample Light Stabiliser          (hours)                                       ______________________________________                                        --    none (control)            800                                           --    2-(2'-hydroxy-3',5'-di-t-butylphenyl)                                                                   1630                                          5-chlorobenzotriazole                                                         136   bis(1,2,2,6,6-pentamethyl-4-                                                                            >9000                                               piperidinyl)sebacate                                                    137   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     10,000                                              β-(3',5'-di-t-butyl-4'-hydroxyphenyl)                                    propionate                                                              138   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     >8600                                               (3',5'-di-t-butyl-4'-hydroxy benzoate)                                  139   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     6500                                                octanoate                                                               140   4-phenylcarbamoyloxy-1,2,2,6,6-pentamethyl                                                              >7000                                               piperidine                                                              141   4-methylcarbamoyloxy-1,2,2,6,6-                                                                         6000                                                pentamethylpiperidine                                                   142   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     >6000                                               cyclohexane-carboxylate                                                 143   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     >6000                                               stearate                                                                144   1,2,2,6,6-pentamethylpiperidinyl-4-                                                                     >5000                                               benzoate                                                                ______________________________________                                    

EXAMPLES 145- 150

100 Parts by weight of polyamide-6pellets containing 1.8 parts by weightof TiO₂ were dryblended with 0.5 part of4-benzyloxy-1,2,2,6,6-pentamethyl piperidine. The resulting mixture wasmelt-spun directly into monofilaments of 20 denier. The monofilamentswere mounted on white cardboard without tension and were exposed tolight radiation in a Xenotest 450 exposure unit.

After 500, 1,000, 1,500 and 2000 hours of exposure time respectively, 5fiber samples of each formulation and time interval were tested fortensile strength. The arithmetic mean percentage values of residualtensile strength were plotted as a function of exposure time. Thefailure points - time to 50% loss of original tensile strength - wereobtained from these graphs.

                  TABLE                                                           ______________________________________                                                                    Time to 50% loss                                                              of original ten-                                  Ex-                         sile strength                                     ample Light Stabiliser      (hours)                                           ______________________________________                                        --    none (control)         475                                              145   4-benzyloxy-1,2,2,6,6-penta-                                                  methylpiperidine      1420                                              146   bis(1,2,2,6,6-pentamethyl-4-                                                  piperidinyl)sebacate  1600                                              147   1,2,2,6,6-pentamethylpiperi-                                                  dinyl-4-octanoate     1450                                              148   1-phenylcarbamoyloxy-1,2,2,6,6-                                               pentamethylpiperidine 1450                                              149   1,6-bis(4'-carbamoyloxy-1',2'-                                                2',6',6'-pentamethylpiperidine)                                               hexane                                                                  150   1,4-bis(1' ,2',2',2',6',6'-penta-                                             methyl-4'-piperidinyloxy)butane                                                                     1600                                              ______________________________________                                    

What we claim is:
 1. A compound having the formula: ##STR155## whereinR^(I) and R^(II) are the same or different and each is a straight orbranched alkyl group, having from 1 to 4 carbon atoms, or R^(I) orR^(II), together with the carbon atom to which they are attached form acycloalkyl group having from 5 to 12 carbon atoms; Y is an alkyl group,having from 5 to 20 carbon atoms, alkenyl having from 7 to 9 carbonatoms, n is 2, R is cycloalkylene having from 1 to 20 carbon atoms,cycloalkylene having from 5 to 12 carbon atoms, arylene, having from 6to 20 carbon atoms, vinylene propenylene, p-xylylene, the group -CH₂ CH₂SCH₂ CH₂ - or R is absent; and a salt thereof selected from phosphate,carbonate, sulfate, chloride, acetate, stearate, maleate, citrate,tertrate, oxalate, benzoate and substituted carbamate.
 2. A compound asclaimed in claim 1 wherein n is 2 and R is a methylene, 1,2-ethylene,1,4-butylene, 1,8n-octylene, 2,2,4-trimethyl-1, 4-butylene,1,10-n-decylene, 1,2-eicosylene, vinylene, propenylene, 1,2-, 1,3- or1,4-cyclohexylene, cyclohexyl-3-ene, 1,2-, 1,3- or 1,4-phenylene,p-xylylene, 1,4- or 1,5-naphthylene, diphenylene or diphenylmethyleneresidue or the group --CH₂ CH₂ SCH₂ CH₂ - or R is absent.
 3. A compoundof claim 2 wherein R^(I) and R^(II) are methyl.